diff --git a/java/google/registry/flows/EppXmlTransformer.java b/java/google/registry/flows/EppXmlTransformer.java
index 8209cf32a..fda260a68 100644
--- a/java/google/registry/flows/EppXmlTransformer.java
+++ b/java/google/registry/flows/EppXmlTransformer.java
@@ -63,7 +63,8 @@ public class EppXmlTransformer  {
       "dsig.xsd",
       "smd.xsd",
       "launch.xsd",
-      "allocate.xsd");
+      "allocate.xsd",
+      "flags.xsd");
 
   private static final XmlTransformer INPUT_TRANSFORMER =
       new XmlTransformer(SCHEMAS, EppInput.class);
diff --git a/java/google/registry/model/BUILD b/java/google/registry/model/BUILD
index 0228ab733..714adc27a 100644
--- a/java/google/registry/model/BUILD
+++ b/java/google/registry/model/BUILD
@@ -16,6 +16,7 @@ FIELD_EXPOSERS = [
     "domain/fee06/FieldExposer.java",
     "domain/fee11/FieldExposer.java",
     "domain/fee12/FieldExposer.java",
+    "domain/flags/FieldExposer.java",
     "domain/launch/FieldExposer.java",
     "domain/rgp/FieldExposer.java",
     "domain/secdns/FieldExposer.java",
diff --git a/java/google/registry/model/domain/flags/FlagsCheckCommandExtension.java b/java/google/registry/model/domain/flags/FlagsCheckCommandExtension.java
new file mode 100644
index 000000000..115be34d1
--- /dev/null
+++ b/java/google/registry/model/domain/flags/FlagsCheckCommandExtension.java
@@ -0,0 +1,33 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.model.domain.flags;
+
+import google.registry.model.eppinput.EppInput.CommandExtension;
+import java.util.List;
+import javax.xml.bind.annotation.XmlElement;
+import javax.xml.bind.annotation.XmlRootElement;
+
+/**
+ * A flags extension that may be present on domain check commands. The extension will specify a
+ * map from domain to a set of flags to be applied to any checks performed on that domain. So if
+ * the client wants to know how much a create would cost on a particular domain with flag X set,
+ * they can send a check command with a flags extension that associates the domain with flag X.
+ * See {@FlagsCreateCommandExtension} for more information about the flags extension.
+ */
+@XmlRootElement(name = "check")
+public class FlagsCheckCommandExtension implements CommandExtension {
+  @XmlElement(name = "domain")
+  List<FlagsCheckCommandExtensionItem> domains;
+}
diff --git a/java/google/registry/model/domain/flags/FlagsCheckCommandExtensionItem.java b/java/google/registry/model/domain/flags/FlagsCheckCommandExtensionItem.java
new file mode 100644
index 000000000..8e26444d2
--- /dev/null
+++ b/java/google/registry/model/domain/flags/FlagsCheckCommandExtensionItem.java
@@ -0,0 +1,32 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.model.domain.flags;
+
+import java.util.List;
+import javax.xml.bind.annotation.XmlElement;
+import javax.xml.bind.annotation.XmlType;
+
+/**
+ * An single domain item in a domain check command flags extension. Each item associates a single
+ * domain with one or more flags. This object appears as part of a list contained in {@link
+ * FlagsCheckCommandExtension}.
+ */
+@XmlType(propOrder = {"name", "flags"})
+public class FlagsCheckCommandExtensionItem {
+  String name;
+
+  @XmlElement(name = "flag")
+  List<String> flags;
+}
diff --git a/java/google/registry/model/domain/flags/FlagsCreateCommandExtension.java b/java/google/registry/model/domain/flags/FlagsCreateCommandExtension.java
new file mode 100644
index 000000000..fadf94107
--- /dev/null
+++ b/java/google/registry/model/domain/flags/FlagsCreateCommandExtension.java
@@ -0,0 +1,33 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.model.domain.flags;
+
+import google.registry.model.eppinput.EppInput.CommandExtension;
+import java.util.List;
+import javax.xml.bind.annotation.XmlElement;
+import javax.xml.bind.annotation.XmlRootElement;
+
+/**
+ * A flags extension that may be present on domain create commands. The extension specifies one or
+ * more flag strings. The extension does not dictate the use of any specific flags, but leaves it up
+ * to the particular TLD-specific logic. Some TLDs have special rules regarding discounts and
+ * eligibility. Such TLDs can define whatever flags they need to use for interacting with the
+ * registrar, and pass them using the flags extension.
+ */
+@XmlRootElement(name = "create")
+public class FlagsCreateCommandExtension implements CommandExtension {
+  @XmlElement(name = "flag")
+  List<String> flags;
+}
diff --git a/java/google/registry/model/domain/flags/FlagsCreateResponseExtension.java b/java/google/registry/model/domain/flags/FlagsCreateResponseExtension.java
new file mode 100644
index 000000000..5882979cc
--- /dev/null
+++ b/java/google/registry/model/domain/flags/FlagsCreateResponseExtension.java
@@ -0,0 +1,32 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.model.domain.flags;
+
+import google.registry.model.eppoutput.EppResponse.ResponseExtension;
+import java.util.List;
+import javax.xml.bind.annotation.XmlElement;
+import javax.xml.bind.annotation.XmlRootElement;
+
+/**
+ * A flags extension that may be present on domain create responses. The extension specifies one or
+ * more flag strings. See {@link FlagsCreateResponseExtension} for more details about the flags
+ * extension. The server may return different flags in the create response than were passed in the
+ * create command, though often they are likely to be the same.
+ */
+@XmlRootElement(name = "creData")
+public class FlagsCreateResponseExtension implements ResponseExtension {
+  @XmlElement(name = "flag")
+  List<String> flags;
+}
diff --git a/java/google/registry/model/domain/flags/FlagsInfoResponseExtension.java b/java/google/registry/model/domain/flags/FlagsInfoResponseExtension.java
new file mode 100644
index 000000000..82b5b5b42
--- /dev/null
+++ b/java/google/registry/model/domain/flags/FlagsInfoResponseExtension.java
@@ -0,0 +1,33 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.model.domain.flags;
+
+import google.registry.model.eppoutput.EppResponse.ResponseExtension;
+import java.util.List;
+import javax.xml.bind.annotation.XmlElement;
+import javax.xml.bind.annotation.XmlRootElement;
+
+/**
+ * A flags extension that may be present on domain info responses. See {@link
+ * FlagsCreateResponseExtension} for more details about the flags extension. Info commands sent by
+ * the registrar do not specify the flags extension, but TLDs which use flags to support specific
+ * functionality can pass them back to the registrar in info responses to indicate the current state
+ * of a domain.
+ */
+@XmlRootElement(name = "infData")
+public class FlagsInfoResponseExtension implements ResponseExtension {
+  @XmlElement(name = "flag")
+  List<String> flags;
+}
diff --git a/java/google/registry/model/domain/flags/FlagsList.java b/java/google/registry/model/domain/flags/FlagsList.java
new file mode 100644
index 000000000..cdb3020e5
--- /dev/null
+++ b/java/google/registry/model/domain/flags/FlagsList.java
@@ -0,0 +1,27 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.model.domain.flags;
+
+import java.util.List;
+import javax.xml.bind.annotation.XmlElement;
+
+/**
+ * A list of flags contained in the add or rem elements of {@link FlagsUpdateCommandExtension} and
+ * {@link FlagsTransferCommandExtension} commands and {@link FlagsPollResponseExtension} responses.
+ */
+public class FlagsList {
+  @XmlElement(name = "flag")
+  List<String> flags;
+}
diff --git a/java/google/registry/model/domain/flags/FlagsPollResponseExtension.java b/java/google/registry/model/domain/flags/FlagsPollResponseExtension.java
new file mode 100644
index 000000000..dc43d7386
--- /dev/null
+++ b/java/google/registry/model/domain/flags/FlagsPollResponseExtension.java
@@ -0,0 +1,32 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.model.domain.flags;
+
+import google.registry.model.eppoutput.EppResponse.ResponseExtension;
+import javax.xml.bind.annotation.XmlRootElement;
+import javax.xml.bind.annotation.XmlType;
+
+/**
+ * A flags extension that may be present on poll responses. See {@link
+ * FlagsCreateResponseExtension} for more details about the flags extension. Poll messages can be
+ * used for TLDs which require flags to support special functionality, to notify registrars about
+ * changes in the status of domains.
+ */
+@XmlRootElement(name = "panData")
+@XmlType(propOrder = {"add", "rem"})
+public class FlagsPollResponseExtension implements ResponseExtension {
+  FlagsList add;
+  FlagsList rem;
+}
diff --git a/java/google/registry/model/domain/flags/FlagsTransferCommandExtension.java b/java/google/registry/model/domain/flags/FlagsTransferCommandExtension.java
new file mode 100644
index 000000000..c55ed796a
--- /dev/null
+++ b/java/google/registry/model/domain/flags/FlagsTransferCommandExtension.java
@@ -0,0 +1,33 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.model.domain.flags;
+
+import google.registry.model.eppinput.EppInput.CommandExtension;
+import javax.xml.bind.annotation.XmlRootElement;
+import javax.xml.bind.annotation.XmlType;
+
+/**
+ * A flags extension that may be present on domain transfer commands. See {@link
+ * FlagsCreateResponseExtension} for more details about the flags extension. For TLDs which require
+ * flags to support special functionality, some flags may need to be modified as part of the
+ * transfer process. In such a case, the extension looks the same as it would for an equivalent
+ * {@link FlagsUpdateCommandExtension} command.
+ */
+@XmlRootElement(name = "transfer")
+@XmlType(propOrder = {"add", "rem"})
+public class FlagsTransferCommandExtension implements CommandExtension {
+  FlagsList add; // list of flags to be added (turned on)
+  FlagsList rem; // list of flags to be removed (turned off)
+}
diff --git a/java/google/registry/model/domain/flags/FlagsUpdateCommandExtension.java b/java/google/registry/model/domain/flags/FlagsUpdateCommandExtension.java
new file mode 100644
index 000000000..a513d0f52
--- /dev/null
+++ b/java/google/registry/model/domain/flags/FlagsUpdateCommandExtension.java
@@ -0,0 +1,33 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.model.domain.flags;
+
+import google.registry.model.eppinput.EppInput.CommandExtension;
+import javax.xml.bind.annotation.XmlRootElement;
+import javax.xml.bind.annotation.XmlType;
+
+/**
+ * A flags extension that may be present on domain update commands. See {@link
+ * FlagsCreateResponseExtension} for more details about the flags extension. For TLDs which require
+ * flags to support special functionality, the registrar can send an update command to change the
+ * state of flags (as allowed by the TLD's logic). Update responses merely acknowledge the update;
+ * an update response does not contain a flags extension.
+ */
+@XmlRootElement(name = "update")
+@XmlType(propOrder = {"add", "rem"})
+public class FlagsUpdateCommandExtension implements CommandExtension {
+  FlagsList add; // list of flags to be added (turned on)
+  FlagsList rem; // list of flags to be removed (turned off)
+}
diff --git a/java/google/registry/model/domain/flags/package-info.java b/java/google/registry/model/domain/flags/package-info.java
new file mode 100644
index 000000000..328b8eaca
--- /dev/null
+++ b/java/google/registry/model/domain/flags/package-info.java
@@ -0,0 +1,26 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+@XmlSchema(
+    namespace = "urn:google:params:xml:ns:flags-0.1",
+    xmlns = @XmlNs(prefix = "flags", namespaceURI = "urn:google:params:xml:ns:flags-0.1"),
+    elementFormDefault = XmlNsForm.QUALIFIED)
+@XmlAccessorType(XmlAccessType.FIELD)
+package google.registry.model.domain.flags;
+
+import javax.xml.bind.annotation.XmlAccessType;
+import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlNs;
+import javax.xml.bind.annotation.XmlNsForm;
+import javax.xml.bind.annotation.XmlSchema;
diff --git a/java/google/registry/model/eppcommon/ProtocolDefinition.java b/java/google/registry/model/eppcommon/ProtocolDefinition.java
index 77d3ebe2f..49c1861a5 100644
--- a/java/google/registry/model/eppcommon/ProtocolDefinition.java
+++ b/java/google/registry/model/eppcommon/ProtocolDefinition.java
@@ -28,6 +28,7 @@ import google.registry.model.domain.fee11.FeeCheckCommandExtensionV11;
 import google.registry.model.domain.fee11.FeeCheckResponseExtensionV11;
 import google.registry.model.domain.fee12.FeeCheckCommandExtensionV12;
 import google.registry.model.domain.fee12.FeeCheckResponseExtensionV12;
+import google.registry.model.domain.flags.FlagsCheckCommandExtension;
 import google.registry.model.domain.launch.LaunchCreateExtension;
 import google.registry.model.domain.metadata.MetadataExtension;
 import google.registry.model.domain.rgp.RgpUpdateExtension;
@@ -57,6 +58,7 @@ public class ProtocolDefinition {
     FEE_0_6(FeeCheckCommandExtensionV06.class, FeeCheckResponseExtensionV06.class, true),
     FEE_0_11(FeeCheckCommandExtensionV11.class, FeeCheckResponseExtensionV11.class, true),
     FEE_0_12(FeeCheckCommandExtensionV12.class, FeeCheckResponseExtensionV12.class, true),
+    FLAGS_0_1(FlagsCheckCommandExtension.class, null, true),
     ALLOCATE_1_0(AllocateCreateExtension.class, null, false),
     METADATA_1_0(MetadataExtension.class, null, false);
 
diff --git a/java/google/registry/model/eppinput/EppInput.java b/java/google/registry/model/eppinput/EppInput.java
index 3552c9bfd..16a660aab 100644
--- a/java/google/registry/model/eppinput/EppInput.java
+++ b/java/google/registry/model/eppinput/EppInput.java
@@ -41,6 +41,10 @@ import google.registry.model.domain.fee12.FeeCreateCommandExtensionV12;
 import google.registry.model.domain.fee12.FeeRenewCommandExtensionV12;
 import google.registry.model.domain.fee12.FeeTransferCommandExtensionV12;
 import google.registry.model.domain.fee12.FeeUpdateCommandExtensionV12;
+import google.registry.model.domain.flags.FlagsCheckCommandExtension;
+import google.registry.model.domain.flags.FlagsCreateCommandExtension;
+import google.registry.model.domain.flags.FlagsTransferCommandExtension;
+import google.registry.model.domain.flags.FlagsUpdateCommandExtension;
 import google.registry.model.domain.launch.LaunchCheckExtension;
 import google.registry.model.domain.launch.LaunchCreateExtension;
 import google.registry.model.domain.launch.LaunchDeleteExtension;
@@ -323,6 +327,10 @@ public class EppInput extends ImmutableObject {
         @XmlElementRef(type = FeeTransferCommandExtensionV12.class),
         @XmlElementRef(type = FeeUpdateCommandExtensionV12.class),
         // other extensions
+        @XmlElementRef(type = FlagsCheckCommandExtension.class),
+        @XmlElementRef(type = FlagsCreateCommandExtension.class),
+        @XmlElementRef(type = FlagsTransferCommandExtension.class),
+        @XmlElementRef(type = FlagsUpdateCommandExtension.class),
         @XmlElementRef(type = LaunchCheckExtension.class),
         @XmlElementRef(type = LaunchCreateExtension.class),
         @XmlElementRef(type = LaunchDeleteExtension.class),
diff --git a/java/google/registry/model/eppoutput/EppResponse.java b/java/google/registry/model/eppoutput/EppResponse.java
index ec95facf8..b15e3aabc 100644
--- a/java/google/registry/model/eppoutput/EppResponse.java
+++ b/java/google/registry/model/eppoutput/EppResponse.java
@@ -41,6 +41,9 @@ import google.registry.model.domain.fee12.FeeDeleteResponseExtensionV12;
 import google.registry.model.domain.fee12.FeeRenewResponseExtensionV12;
 import google.registry.model.domain.fee12.FeeTransferResponseExtensionV12;
 import google.registry.model.domain.fee12.FeeUpdateResponseExtensionV12;
+import google.registry.model.domain.flags.FlagsCreateResponseExtension;
+import google.registry.model.domain.flags.FlagsInfoResponseExtension;
+import google.registry.model.domain.flags.FlagsPollResponseExtension;
 import google.registry.model.domain.launch.LaunchCheckResponseExtension;
 import google.registry.model.domain.launch.LaunchCreateResponseExtension;
 import google.registry.model.domain.launch.LaunchInfoResponseExtension;
@@ -152,6 +155,9 @@ public class EppResponse extends ImmutableObject implements ResponseOrGreeting {
       @XmlElementRef(type = FeeRenewResponseExtensionV12.class),
       @XmlElementRef(type = FeeTransferResponseExtensionV12.class),
       @XmlElementRef(type = FeeUpdateResponseExtensionV12.class),
+      @XmlElementRef(type = FlagsCreateResponseExtension.class),
+      @XmlElementRef(type = FlagsInfoResponseExtension.class),
+      @XmlElementRef(type = FlagsPollResponseExtension.class),
       @XmlElementRef(type = LaunchCheckResponseExtension.class),
       @XmlElementRef(type = LaunchCreateResponseExtension.class),
       @XmlElementRef(type = LaunchInfoResponseExtension.class),
diff --git a/java/google/registry/xjc/bindings.xjb b/java/google/registry/xjc/bindings.xjb
index c46406180..9e75950b0 100644
--- a/java/google/registry/xjc/bindings.xjb
+++ b/java/google/registry/xjc/bindings.xjb
@@ -51,6 +51,15 @@
       </nameXmlTransform>
     </schemaBindings>
   </bindings>
+  <bindings schemaLocation="flags.xsd" node="/xsd:schema">
+    <schemaBindings>
+      <package name="google.registry.xjc.flags"/>
+      <nameXmlTransform>
+        <elementName prefix="XjcDomain"/>
+        <typeName prefix="XjcDomain"/>
+      </nameXmlTransform>
+    </schemaBindings>
+  </bindings>
   <bindings schemaLocation="host.xsd" node="/xsd:schema">
     <schemaBindings>
       <package name="google.registry.xjc.host"/>
diff --git a/java/google/registry/xml/xsd/flags.xsd b/java/google/registry/xml/xsd/flags.xsd
new file mode 100644
index 000000000..6cc67312d
--- /dev/null
+++ b/java/google/registry/xml/xsd/flags.xsd
@@ -0,0 +1,73 @@
+<?xml version="1.0" encoding="utf-8"?>
+<schema xmlns="http://www.w3.org/2001/XMLSchema"
+  xmlns:flags="urn:google:params:xml:ns:flags-0.1"
+  xmlns:eppcom="urn:ietf:params:xml:ns:eppcom-1.0"
+  targetNamespace="urn:google:params:xml:ns:flags-0.1"
+  elementFormDefault="qualified">
+
+  <import namespace="urn:ietf:params:xml:ns:eppcom-1.0" />
+
+  <annotation>
+    <documentation>
+      Extensible Provisioning Protocol v1.0 domain name extension schema for custom flags.
+    </documentation>
+  </annotation>
+
+  <!--
+  List of flags
+  -->
+  <complexType name="flagListType">
+    <sequence>
+      <element name="flag" type="eppcom:minTokenType"
+          minOccurs="0" maxOccurs="unbounded" />
+    </sequence>
+  </complexType>
+
+  <!--
+  <check>: client command contains list of objects and their associated flags;
+  server response unchanged
+  -->
+  <element name="check" type="flags:checkType" />
+
+  <complexType name="checkType">
+    <sequence>
+      <element name="domain" type="flags:domainCheckType"
+        maxOccurs="unbounded" />
+    </sequence>
+  </complexType>
+
+  <complexType name="domainCheckType">
+    <sequence>
+      <element name="name" type="eppcom:labelType" />
+      <element name="flag" type="eppcom:minTokenType"
+        minOccurs="0" maxOccurs="unbounded" />
+    </sequence>
+  </complexType>
+
+  <!--
+  <info>: client command unchanged, server response contains list of flags
+  -->
+  <element name="infData" type="flags:flagListType" />
+
+  <!--
+  <create>: client command and server response contain lists of flags
+  -->
+  <element name="create" type="flags:flagListType" />
+  <element name="creData" type="flags:flagListType" />
+
+  <!--
+  <update> and <transfer>: client command contains list of flags to add or
+  remove; server response unchanged
+  <poll>: client command unchanged; server response may list flag state changes
+  -->
+  <element name="transfer" type="flags:flagChangesType" />
+  <element name="update" type="flags:flagChangesType" />
+  <element name="panData" type="flags:flagChangesType" />
+
+  <complexType name="flagChangesType">
+    <sequence>
+      <element name="add" type="flags:flagListType" minOccurs="0"/>
+      <element name="rem" type="flags:flagListType" minOccurs="0"/>
+    </sequence>
+  </complexType>
+</schema>
diff --git a/javatests/google/registry/flows/session/testdata/greeting_crr.xml b/javatests/google/registry/flows/session/testdata/greeting_crr.xml
index 874cfc0d3..4c469f415 100644
--- a/javatests/google/registry/flows/session/testdata/greeting_crr.xml
+++ b/javatests/google/registry/flows/session/testdata/greeting_crr.xml
@@ -15,6 +15,7 @@
         <extURI>urn:ietf:params:xml:ns:fee-0.6</extURI>
         <extURI>urn:ietf:params:xml:ns:fee-0.11</extURI>
         <extURI>urn:ietf:params:xml:ns:fee-0.12</extURI>
+        <extURI>urn:google:params:xml:ns:flags-0.1</extURI>
       </svcExtension>
     </svcMenu>
     <dcp>
diff --git a/javatests/google/registry/flows/testdata/greeting_crr.xml b/javatests/google/registry/flows/testdata/greeting_crr.xml
index 874cfc0d3..4c469f415 100644
--- a/javatests/google/registry/flows/testdata/greeting_crr.xml
+++ b/javatests/google/registry/flows/testdata/greeting_crr.xml
@@ -15,6 +15,7 @@
         <extURI>urn:ietf:params:xml:ns:fee-0.6</extURI>
         <extURI>urn:ietf:params:xml:ns:fee-0.11</extURI>
         <extURI>urn:ietf:params:xml:ns:fee-0.12</extURI>
+        <extURI>urn:google:params:xml:ns:flags-0.1</extURI>
       </svcExtension>
     </svcMenu>
     <dcp>
diff --git a/javatests/google/registry/model/domain/DomainCommandTest.java b/javatests/google/registry/model/domain/DomainCommandTest.java
index 3c49367cf..c3fcf3695 100644
--- a/javatests/google/registry/model/domain/DomainCommandTest.java
+++ b/javatests/google/registry/model/domain/DomainCommandTest.java
@@ -59,6 +59,11 @@ public class DomainCommandTest extends ResourceCommandTestCase {
     doXmlRoundtripTest("domain_create_fee.xml");
   }
 
+  @Test
+  public void testCreate_flags() throws Exception {
+    doXmlRoundtripTest("domain_create_flags.xml");
+  }
+
   @Test
   public void testDelete() throws Exception {
     doXmlRoundtripTest("domain_delete.xml");
@@ -74,6 +79,11 @@ public class DomainCommandTest extends ResourceCommandTestCase {
     doXmlRoundtripTest("domain_update_fee.xml");
   }
 
+  @Test
+  public void testUpdate_flags() throws Exception {
+    doXmlRoundtripTest("domain_update_flags.xml");
+  }
+
   @Test
   public void testInfo() throws Exception {
     doXmlRoundtripTest("domain_info.xml");
@@ -119,6 +129,11 @@ public class DomainCommandTest extends ResourceCommandTestCase {
     doXmlRoundtripTest("domain_check_fee.xml");
   }
 
+  @Test
+  public void testCheck_flags() throws Exception {
+    doXmlRoundtripTest("domain_check_flags.xml");
+  }
+
   @Test
   public void testTransferApprove() throws Exception {
     doXmlRoundtripTest("domain_transfer_approve.xml");
@@ -149,6 +164,11 @@ public class DomainCommandTest extends ResourceCommandTestCase {
     doXmlRoundtripTest("domain_transfer_request_fee.xml");
   }
 
+  @Test
+  public void testTransferRequest_flags() throws Exception {
+    doXmlRoundtripTest("domain_transfer_request_flags.xml");
+  }
+
   @Test
   public void testRenew() throws Exception {
     doXmlRoundtripTest("domain_renew.xml");
diff --git a/javatests/google/registry/model/domain/testdata/domain_check_flags.xml b/javatests/google/registry/model/domain/testdata/domain_check_flags.xml
new file mode 100644
index 000000000..9a507f5e4
--- /dev/null
+++ b/javatests/google/registry/model/domain/testdata/domain_check_flags.xml
@@ -0,0 +1,26 @@
+<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
+  <command>
+    <check>
+      <domain:check
+        xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
+        <domain:name>example.com</domain:name>
+        <domain:name>example.net</domain:name>
+        <domain:name>example.org</domain:name>
+      </domain:check>
+    </check>
+    <extension>
+      <flags:check xmlns:flags="urn:google:params:xml:ns:flags-0.1">
+        <flags:domain>
+          <flags:name>example.com</flags:name>
+          <flags:flag>one</flags:flag>
+        </flags:domain>
+        <flags:domain>
+          <flags:name>example.net</flags:name>
+          <flags:flag>two</flags:flag>
+          <flags:flag>three</flags:flag>
+        </flags:domain>
+      </flags:check>
+    </extension>
+    <clTRID>ABC-12345</clTRID>
+  </command>
+</epp>
diff --git a/javatests/google/registry/model/domain/testdata/domain_create_flags.xml b/javatests/google/registry/model/domain/testdata/domain_create_flags.xml
new file mode 100644
index 000000000..a4459d103
--- /dev/null
+++ b/javatests/google/registry/model/domain/testdata/domain_create_flags.xml
@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="utf-8" standalone="no"?>
+<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
+  <command>
+    <create>
+      <domain:create
+        xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
+        <domain:name>example.com</domain:name>
+        <domain:period unit="y">2</domain:period>
+        <domain:ns>
+          <domain:hostObj>ns1.example.net</domain:hostObj>
+          <domain:hostObj>ns2.example.net</domain:hostObj>
+        </domain:ns>
+        <domain:registrant>jd1234</domain:registrant>
+        <domain:contact type="admin">sh8013</domain:contact>
+        <domain:contact type="tech">sh8013</domain:contact>
+        <domain:authInfo>
+          <domain:pw>2fooBAR</domain:pw>
+        </domain:authInfo>
+      </domain:create>
+    </create>
+    <extension>
+      <flags:create xmlns:flags="urn:google:params:xml:ns:flags-0.1">
+        <flags:flag>one</flags:flag>
+        <flags:flag>two</flags:flag>
+      </flags:create>
+    </extension>
+    <clTRID>ABC-12345</clTRID>
+  </command>
+</epp>
diff --git a/javatests/google/registry/model/domain/testdata/domain_transfer_request_flags.xml b/javatests/google/registry/model/domain/testdata/domain_transfer_request_flags.xml
new file mode 100644
index 000000000..464bce1aa
--- /dev/null
+++ b/javatests/google/registry/model/domain/testdata/domain_transfer_request_flags.xml
@@ -0,0 +1,26 @@
+<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
+  <command>
+    <transfer op="request">
+      <domain:transfer
+       xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
+        <domain:name>example.com</domain:name>
+        <domain:period unit="y">1</domain:period>
+        <domain:authInfo>
+          <domain:pw roid="JD1234-REP">2fooBAR</domain:pw>
+        </domain:authInfo>
+      </domain:transfer>
+    </transfer>
+    <extension>
+      <flags:transfer xmlns:flags="urn:google:params:xml:ns:flags-0.1">
+        <flags:add>
+          <flags:flag>addFlag</flags:flag>
+        </flags:add>
+        <flags:rem>
+          <flags:flag>remFlag1</flags:flag>
+          <flags:flag>remFlag2</flags:flag>
+        </flags:rem>
+      </flags:transfer>
+    </extension>
+    <clTRID>ABC-12345</clTRID>
+  </command>
+</epp>
diff --git a/javatests/google/registry/model/domain/testdata/domain_update_flags.xml b/javatests/google/registry/model/domain/testdata/domain_update_flags.xml
new file mode 100644
index 000000000..ca6c23f8c
--- /dev/null
+++ b/javatests/google/registry/model/domain/testdata/domain_update_flags.xml
@@ -0,0 +1,42 @@
+<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
+  <command>
+    <update>
+      <domain:update
+       xmlns:domain="urn:ietf:params:xml:ns:domain-1.0">
+        <domain:name>example.com</domain:name>
+        <domain:add>
+          <domain:ns>
+            <domain:hostObj>ns2.example.com</domain:hostObj>
+          </domain:ns>
+          <domain:contact type="tech">mak21</domain:contact>
+          <domain:status s="clientHold"/>
+        </domain:add>
+        <domain:rem>
+          <domain:ns>
+            <domain:hostObj>ns1.example.com</domain:hostObj>
+          </domain:ns>
+          <domain:contact type="tech">sh8013</domain:contact>
+          <domain:status s="clientUpdateProhibited"/>
+        </domain:rem>
+        <domain:chg>
+          <domain:registrant>sh8013</domain:registrant>
+          <domain:authInfo>
+            <domain:pw>2BARfoo</domain:pw>
+          </domain:authInfo>
+        </domain:chg>
+      </domain:update>
+    </update>
+    <extension>
+      <flags:update xmlns:flags="urn:google:params:xml:ns:flags-0.1">
+        <flags:add>
+          <flags:flag>addFlag</flags:flag>
+        </flags:add>
+        <flags:rem>
+          <flags:flag>remFlag1</flags:flag>
+          <flags:flag>remFlag2</flags:flag>
+        </flags:rem>
+      </flags:update>
+    </extension>
+    <clTRID>ABC-12345</clTRID>
+  </command>
+</epp>