diff --git a/web/modals/threads/members/change-member-role-modal.react.js b/web/modals/threads/members/change-member-role-modal.react.js
index 2d0229bce..74bb0079f 100644
--- a/web/modals/threads/members/change-member-role-modal.react.js
+++ b/web/modals/threads/members/change-member-role-modal.react.js
@@ -1,88 +1,128 @@
 // @flow
 
 import invariant from 'invariant';
 import * as React from 'react';
 
+import {
+  changeThreadMemberRoles,
+  changeThreadMemberRolesActionTypes,
+} from 'lib/actions/thread-actions.js';
 import { useModalContext } from 'lib/components/modal-provider.react.js';
 import type { RelativeMemberInfo, ThreadInfo } from 'lib/types/thread-types';
+import {
+  useDispatchActionPromise,
+  useServerCall,
+} from 'lib/utils/action-utils.js';
 import { values } from 'lib/utils/objects.js';
 
 import css from './change-member-role-modal.css';
 import UserAvatar from '../../../avatars/user-avatar.react.js';
 import Button, { buttonThemes } from '../../../components/button.react.js';
 import Dropdown from '../../../components/dropdown.react.js';
 import Modal from '../../modal.react.js';
 import UnsavedChangesModal from '../../unsaved-changes-modal.react.js';
 
 type ChangeMemberRoleModalProps = {
   +memberInfo: RelativeMemberInfo,
   +threadInfo: ThreadInfo,
 };
 
 function ChangeMemberRoleModal(props: ChangeMemberRoleModalProps): React.Node {
   const { memberInfo, threadInfo } = props;
   const { pushModal, popModal } = useModalContext();
+  const dispatchActionPromise = useDispatchActionPromise();
+  const callChangeThreadMemberRoles = useServerCall(changeThreadMemberRoles);
 
   const roleOptions = React.useMemo(
     () =>
       values(threadInfo.roles).map(role => ({
         id: role.id,
         name: role.name,
       })),
     [threadInfo.roles],
   );
 
   const initialSelectedRole = memberInfo.role;
   invariant(initialSelectedRole, "Member's role must be defined");
 
   const [selectedRole, setSelectedRole] = React.useState(initialSelectedRole);
 
   const onBackClick = React.useCallback(() => {
     if (selectedRole === initialSelectedRole) {
       popModal();
       return;
     }
 
     pushModal(<UnsavedChangesModal />);
   }, [initialSelectedRole, popModal, pushModal, selectedRole]);
 
+  const onSave = React.useCallback(() => {
+    if (selectedRole === initialSelectedRole) {
+      popModal();
+      return;
+    }
+
+    const createChangeThreadMemberRolesPromise = () => {
+      return callChangeThreadMemberRoles(
+        threadInfo.id,
+        [memberInfo.id],
+        selectedRole,
+      );
+    };
+
+    dispatchActionPromise(
+      changeThreadMemberRolesActionTypes,
+      createChangeThreadMemberRolesPromise(),
+    );
+    popModal();
+  }, [
+    callChangeThreadMemberRoles,
+    dispatchActionPromise,
+    initialSelectedRole,
+    memberInfo.id,
+    popModal,
+    selectedRole,
+    threadInfo.id,
+  ]);
+
   return (
     <Modal name="Change Role" onClose={popModal} size="large">
       <div className={css.roleModalDescription}>
         Members can only be assigned to one role at a time. Changing a
         member&rsquo;s role will replace their previously assigned role.
       </div>
       <div className={css.roleModalMember}>
         <div className={css.roleModalMemberAvatar}>
           <UserAvatar userID={memberInfo.id} size="large" />
         </div>
         <div className={css.roleModalMemberName}>{memberInfo.username}</div>
       </div>
       <div className={css.roleModalRoleSelector}>
         <Dropdown
           options={roleOptions}
           activeSelection={selectedRole}
           setActiveSelection={setSelectedRole}
         />
       </div>
       <div className={css.roleModalActionButtons}>
         <Button
           variant="outline"
           className={css.roleModalBackButton}
           onClick={onBackClick}
         >
           Back
         </Button>
         <Button
           variant="filled"
           className={css.roleModalSaveButton}
           buttonColor={buttonThemes.primary}
+          onClick={onSave}
         >
           Save
         </Button>
       </div>
     </Modal>
   );
 }
 
 export default ChangeMemberRoleModal;