diff --git a/keyserver/src/creators/role-creator.js b/keyserver/src/creators/role-creator.js
--- a/keyserver/src/creators/role-creator.js
+++ b/keyserver/src/creators/role-creator.js
@@ -27,6 +27,7 @@
 } from '../fetchers/thread-fetchers.js';
 import { checkThreadPermission } from '../fetchers/thread-permission-fetchers.js';
 import type { Viewer } from '../session/viewer.js';
+import { updateRole } from '../updaters/thread-updaters.js';
 
 type InitialRoles = {
   +default: RoleInfo,
@@ -93,7 +94,7 @@
     throw new ServerError('invalid_credentials');
   }
 
-  const { community, name, permissions, action } = request;
+  const { community, existingRoleID, name, permissions, action } = request;
 
   for (const permission of permissions) {
     if (!userSurfacedPermissionsSet.has(permission)) {
@@ -141,11 +142,37 @@
       VALUES (${row})
     `;
   } else if (action === 'edit_role') {
-    throw new ServerError("unimplemented: can't edit roles yet");
+    query = SQL`
+      UPDATE roles
+      SET name = ${name}, permissions = ${permissionsBlob}
+      WHERE id = ${existingRoleID}
+    `;
   }
 
   await dbQuery(query);
 
+  // The `updateRole` needs to occur after the role has been updated
+  // in the database because it will want the most up to date role info
+  // (permissions / name)
+  if (action === 'edit_role') {
+    if (!existingRoleID) {
+      throw new ServerError('invalid_parameters');
+    }
+
+    const membersWithRole = threadInfo.members.filter(
+      memberInfo => memberInfo.role === existingRoleID,
+    );
+    await updateRole(
+      viewer,
+      {
+        threadID: community,
+        role: existingRoleID,
+        memberIDs: membersWithRole.map(memberInfo => memberInfo.id),
+      },
+      { silenceNewMessages: true },
+    );
+  }
+
   const fetchServerThreadInfosResult = await fetchServerThreadInfos({
     threadID: community,
   });
diff --git a/keyserver/src/responders/thread-responders.js b/keyserver/src/responders/thread-responders.js
--- a/keyserver/src/responders/thread-responders.js
+++ b/keyserver/src/responders/thread-responders.js
@@ -353,6 +353,7 @@
 
 const roleModificationRequestInputValidator = tShape<RoleModificationRequest>({
   community: tID,
+  existingRoleID: t.maybe(tID),
   name: t.String,
   permissions: t.list(userSurfacedPermissionValidator),
   action: t.enums.of(['create_role', 'edit_role']),
diff --git a/keyserver/src/updaters/thread-permission-updaters.js b/keyserver/src/updaters/thread-permission-updaters.js
--- a/keyserver/src/updaters/thread-permission-updaters.js
+++ b/keyserver/src/updaters/thread-permission-updaters.js
@@ -194,14 +194,10 @@
   for (const userID of userIDs) {
     const existingMembership = existingMembershipInfo.get(userID);
     const oldRole = existingMembership?.oldRole ?? '-1';
-    const oldPermissions = existingMembership?.oldPermissions ?? null;
     const oldPermissionsForChildren =
       existingMembership?.oldPermissionsForChildren ?? null;
 
-    if (existingMembership && oldRole === intendedRole) {
-      // If the old role is the same as the new one, we have nothing to update
-      continue;
-    } else if (Number(oldRole) > 0 && role === null) {
+    if (Number(oldRole) > 0 && role === null) {
       // In the case where we're just trying to add somebody to a thread, if
       // they already have a role with a nonzero role then we don't need to do
       // anything
@@ -248,15 +244,6 @@
           'missing',
       );
     }
-    if (
-      existingMembership &&
-      _isEqual(permissions)(oldPermissions) &&
-      oldRole === newRole
-    ) {
-      // This thread and all of its descendants need no updates for this user,
-      // since the corresponding memberships row is unchanged by this operation
-      continue;
-    }
 
     if (permissions) {
       membershipRows.push({
diff --git a/keyserver/src/updaters/thread-updaters.js b/keyserver/src/updaters/thread-updaters.js
--- a/keyserver/src/updaters/thread-updaters.js
+++ b/keyserver/src/updaters/thread-updaters.js
@@ -62,10 +62,16 @@
 import type { Viewer } from '../session/viewer.js';
 import RelationshipChangeset from '../utils/relationship-changeset.js';
 
+type UpdateRoleOptions = {
+  +silenceNewMessages?: boolean,
+};
 async function updateRole(
   viewer: Viewer,
   request: RoleChangeRequest,
+  options?: UpdateRoleOptions,
 ): Promise<ChangeThreadSettingsResult> {
+  const silenceNewMessages = options?.silenceNewMessages;
+
   if (!viewer.loggedIn) {
     throw new ServerError('not_logged_in');
   }
@@ -148,7 +154,10 @@
     newRole: request.role,
     roleName: threadInfo.roles[request.role].name,
   };
-  const newMessageInfos = await createMessages(viewer, [messageData]);
+  let newMessageInfos = [];
+  if (!silenceNewMessages) {
+    newMessageInfos = await createMessages(viewer, [messageData]);
+  }
 
   return { updatesResult: { newUpdates: viewerUpdates }, newMessageInfos };
 }
diff --git a/lib/types/thread-types.js b/lib/types/thread-types.js
--- a/lib/types/thread-types.js
+++ b/lib/types/thread-types.js
@@ -428,6 +428,7 @@
 
 export type RoleModificationRequest = {
   +community: string,
+  +existingRoleID: ?string,
   +name: string,
   +permissions: $ReadOnlyArray<UserSurfacedPermission>,
   +action: 'create_role' | 'edit_role',
diff --git a/native/roles/create-roles-header-right-button.react.js b/native/roles/create-roles-header-right-button.react.js
--- a/native/roles/create-roles-header-right-button.react.js
+++ b/native/roles/create-roles-header-right-button.react.js
@@ -23,7 +23,8 @@
 };
 
 function CreateRolesHeaderRightButton(props: Props): React.Node {
-  const { threadInfo, action, roleName, rolePermissions } = props.route.params;
+  const { threadInfo, action, existingRoleID, roleName, rolePermissions } =
+    props.route.params;
   const navigation = useNavigation();
   const styles = useStyles(unboundStyles);
 
@@ -32,7 +33,7 @@
 
   const onPressCreate = React.useCallback(() => {
     const threadRoleNames = values(threadInfo.roles).map(role => role.name);
-    if (threadRoleNames.includes(roleName)) {
+    if (threadRoleNames.includes(roleName) && action === 'create_role') {
       displayActionResultModal(
         'There is already a role with this name in the community',
       );
@@ -43,6 +44,7 @@
       modifyCommunityRoleActionTypes,
       callModifyCommunityRole({
         community: threadInfo.id,
+        existingRoleID,
         action,
         name: roleName,
         permissions: rolePermissions,
@@ -55,11 +57,13 @@
     dispatchActionPromise,
     threadInfo,
     action,
+    existingRoleID,
     roleName,
     rolePermissions,
     navigation,
   ]);
 
+  const headerRightText = action === 'create_role' ? 'Create' : 'Save';
   const shouldHeaderRightBeDisabled = roleName.length === 0;
   const createButton = React.useMemo(() => {
     const textStyle = shouldHeaderRightBeDisabled
@@ -71,11 +75,12 @@
         onPress={onPressCreate}
         disabled={shouldHeaderRightBeDisabled}
       >
-        <Text style={textStyle}>Create</Text>
+        <Text style={textStyle}>{headerRightText}</Text>
       </TouchableOpacity>
     );
   }, [
     shouldHeaderRightBeDisabled,
+    headerRightText,
     styles.createButtonDisabled,
     styles.createButton,
     onPressCreate,
diff --git a/native/roles/create-roles-screen.react.js b/native/roles/create-roles-screen.react.js
--- a/native/roles/create-roles-screen.react.js
+++ b/native/roles/create-roles-screen.react.js
@@ -28,6 +28,7 @@
 export type CreateRolesScreenParams = {
   +threadInfo: ThreadInfo,
   +action: 'create_role' | 'edit_role',
+  +existingRoleID?: string,
   +roleName: string,
   +rolePermissions: $ReadOnlyArray<UserSurfacedPermission>,
 };
@@ -45,6 +46,7 @@
   const {
     threadInfo,
     action,
+    existingRoleID,
     roleName: defaultRoleName,
     rolePermissions: defaultRolePermissions,
   } = props.route.params;
@@ -111,10 +113,18 @@
       props.navigation.setParams({
         threadInfo,
         action,
+        existingRoleID,
         roleName: customRoleName,
         rolePermissions: selectedPermissions,
       }),
-    [props.navigation, threadInfo, action, customRoleName, selectedPermissions],
+    [
+      props.navigation,
+      threadInfo,
+      action,
+      existingRoleID,
+      customRoleName,
+      selectedPermissions,
+    ],
   );
 
   const modifiedUserSurfacedPermissionOptions = React.useMemo(
diff --git a/native/roles/role-panel-entry.react.js b/native/roles/role-panel-entry.react.js
--- a/native/roles/role-panel-entry.react.js
+++ b/native/roles/role-panel-entry.react.js
@@ -1,6 +1,7 @@
 // @flow
 
 import { useActionSheet } from '@expo/react-native-action-sheet';
+import invariant from 'invariant';
 import * as React from 'react';
 import { View, Text, TouchableOpacity, Platform } from 'react-native';
 import { useSafeAreaInsets } from 'react-native-safe-area-context';
@@ -28,6 +29,15 @@
     props;
   const styles = useStyles(unboundStyles);
 
+  const existingRoleID = React.useMemo(
+    () =>
+      Object.keys(threadInfo.roles).find(
+        roleID => threadInfo.roles[roleID].name === roleName,
+      ),
+    [roleName, threadInfo.roles],
+  );
+  invariant(existingRoleID, 'Role ID must exist for an existing role');
+
   const options = React.useMemo(() => {
     const availableOptions = ['Edit role'];
 
@@ -50,12 +60,20 @@
         navigation.navigate(CreateRolesScreenRouteName, {
           threadInfo,
           action: 'edit_role',
+          existingRoleID,
           roleName,
           rolePermissions,
         });
       }
     },
-    [navigation, options, roleName, rolePermissions, threadInfo],
+    [
+      navigation,
+      options,
+      existingRoleID,
+      roleName,
+      rolePermissions,
+      threadInfo,
+    ],
   );
 
   const activeTheme = useSelector(state => state.globalThemeInfo.activeTheme);