diff --git a/src/commands/CommandHandler.ts b/src/commands/CommandHandler.ts
index fea8811d..14a5f631 100644
--- a/src/commands/CommandHandler.ts
+++ b/src/commands/CommandHandler.ts
@@ -39,6 +39,7 @@ import {
     execConfigSetProtection, execConfigAddProtection, execConfigRemoveProtection
 } from "./ProtectionsCommands";
 import { execSetPowerLevelCommand } from "./SetPowerLevelCommand";
+import { execSetDisplayNameCommand } from "./SetDisplayNameCommand";
 import { execResolveCommand } from "./ResolveAlias";
 import { execKickCommand } from "./KickCommand";
 import { parse as tokenize } from "shell-quote";
@@ -120,11 +121,13 @@ export async function handleCommand(roomId: string, event: { content: { body: st
             return await execSinceCommand(roomId, event, mjolnir, tokens);
         } else if (parts[1] === 'kick' && parts.length > 2) {
             return await execKickCommand(roomId, event, mjolnir, parts);
+        } else if (parts[1] === 'displayname' && parts.length > 2) {
+            return await execSetDisplayNameCommand(roomId, event, mjolnir, parts);
         } else {
             const readItems = readCommand(cmd).slice(1); // remove "!mjolnir"
             const stream = new ArgumentStream(readItems);
             const command = commandTable.findAMatchingCommand(stream)
-            ?? findTableCommand("mjolnir", "help");
+                ?? findTableCommand("mjolnir", "help");
             const adaptor = findMatrixInterfaceAdaptor(command);
             const mjolnirContext: MjolnirContext = {
                 mjolnir, roomId, event, client: mjolnir.client, emitter: mjolnir.matrixEmitter,
diff --git a/src/commands/Help.tsx b/src/commands/Help.tsx
index fbf911e9..2422ea90 100644
--- a/src/commands/Help.tsx
+++ b/src/commands/Help.tsx
@@ -35,28 +35,29 @@ import { defineMatrixInterfaceAdaptor } from "./interface-manager/MatrixInterfac
 import { renderMatrixAndSend } from "./interface-manager/DeadDocumentMatrix";
 
 const oldHelpMenu = "" +
-"!mjolnir                                                            - Print status information\n" +
-"!mjolnir status                                                     - Print status information\n" +
-"!mjolnir status protection <protection> [subcommand]                - Print status information for a protection\n" +
-"!mjolnir redact <user ID> [room alias/ID] [limit]                   - Redacts messages by the sender in the target room (or all rooms), up to a maximum number of events in the backlog (default 1000)\n" +
-"!mjolnir redact <event permalink>                                   - Redacts a message by permalink\n" +
-"!mjolnir kick <glob> [room alias/ID] [reason]                       - Kicks a user or all of those matching a glob in a particular room or all protected rooms\n" +
-"!mjolnir sync                                                       - Force updates of all lists and re-apply rules\n" +
-"!mjolnir verify                                                     - Ensures Mjolnir can moderate all your rooms\n" +
-"!mjolnir list create <shortcode> <alias localpart>                  - Creates a new ban list with the given shortcode and alias\n" +
-"!mjolnir import <room alias/ID> <list shortcode>                    - Imports bans and ACLs into the given list\n" +
-"!mjolnir default <shortcode>                                        - Sets the default list for commands\n" +
-"!mjolnir protections                                                - List all available protections\n" +
-"!mjolnir enable <protection>                                        - Enables a particular protection\n" +
-"!mjolnir disable <protection>                                       - Disables a particular protection\n" +
-"!mjolnir config set <protection>.<setting> [value]                  - Change a protection setting\n" +
-"!mjolnir config add <protection>.<setting> [value]                  - Add a value to a list protection setting\n" +
-"!mjolnir config remove <protection>.<setting> [value]               - Remove a value from a list protection setting\n" +
-"!mjolnir config get [protection]                                    - List protection settings\n" +
-"!mjolnir resolve <room alias>                                       - Resolves a room alias to a room ID\n" +
-"!mjolnir since <date>/<duration> <action> <limit> [rooms...] [reason] - Apply an action ('kick', 'ban', 'mute', 'unmute' or 'show') to all users who joined a room since <date>/<duration> (up to <limit> users)\n" +
-"!mjolnir powerlevel <user ID> <power level> [room alias/ID]         - Sets the power level of the user in the specified room (or all protected rooms)\n" +
-"!mjolnir help                                                       - This menu\n";
+    "!mjolnir                                                            - Print status information\n" +
+    "!mjolnir status                                                     - Print status information\n" +
+    "!mjolnir status protection <protection> [subcommand]                - Print status information for a protection\n" +
+    "!mjolnir redact <user ID> [room alias/ID] [limit]                   - Redacts messages by the sender in the target room (or all rooms), up to a maximum number of events in the backlog (default 1000)\n" +
+    "!mjolnir redact <event permalink>                                   - Redacts a message by permalink\n" +
+    "!mjolnir kick <glob> [room alias/ID] [reason]                       - Kicks a user or all of those matching a glob in a particular room or all protected rooms\n" +
+    "!mjolnir sync                                                       - Force updates of all lists and re-apply rules\n" +
+    "!mjolnir verify                                                     - Ensures Mjolnir can moderate all your rooms\n" +
+    "!mjolnir list create <shortcode> <alias localpart>                  - Creates a new ban list with the given shortcode and alias\n" +
+    "!mjolnir import <room alias/ID> <list shortcode>                    - Imports bans and ACLs into the given list\n" +
+    "!mjolnir default <shortcode>                                        - Sets the default list for commands\n" +
+    "!mjolnir protections                                                - List all available protections\n" +
+    "!mjolnir enable <protection>                                        - Enables a particular protection\n" +
+    "!mjolnir disable <protection>                                       - Disables a particular protection\n" +
+    "!mjolnir config set <protection>.<setting> [value]                  - Change a protection setting\n" +
+    "!mjolnir config add <protection>.<setting> [value]                  - Add a value to a list protection setting\n" +
+    "!mjolnir config remove <protection>.<setting> [value]               - Remove a value from a list protection setting\n" +
+    "!mjolnir config get [protection]                                    - List protection settings\n" +
+    "!mjolnir resolve <room alias>                                       - Resolves a room alias to a room ID\n" +
+    "!mjolnir since <date>/<duration> <action> <limit> [rooms...] [reason] - Apply an action ('kick', 'ban', 'mute', 'unmute' or 'show') to all users who joined a room since <date>/<duration> (up to <limit> users)\n" +
+    "!mjolnir powerlevel <user ID> <power level> [room alias/ID]         - Sets the power level of the user in the specified room (or all protected rooms)\n" +
+    "!mjolnir displayname <displayname>                                  - Sets the displayname of the draupnir instance to the specified value in all rooms.\n" +
+    "!mjolnir help                                                       - This menu\n";
 
 function renderTableHelp(table: CommandTable): DocumentNode {
     // FIXME: is it possible to force case of table names?
@@ -82,14 +83,14 @@ function renderMjolnirHelp(mjolnirTable: CommandTable): DocumentNode {
 defineInterfaceCommand({
     parameters: parameters([], new RestDescription('command parts', findPresentationType("any"))),
     table: "mjolnir",
-    command: async function() { return CommandResult.Ok(findCommandTable("mjolnir")) },
+    command: async function () { return CommandResult.Ok(findCommandTable("mjolnir")) },
     designator: ["help"],
     summary: "Display this message"
 })
 
 defineMatrixInterfaceAdaptor({
     interfaceCommand: findTableCommand("mjolnir", "help"),
-    renderer: async function(client, commandRoomId, event, result) {
+    renderer: async function (client, commandRoomId, event, result) {
         if (result.isErr()) {
             throw new TypeError("This command isn't supposed to fail");
         }
diff --git a/src/commands/SetDisplayNameCommand.ts b/src/commands/SetDisplayNameCommand.ts
index e69de29b..e6b96461 100644
--- a/src/commands/SetDisplayNameCommand.ts
+++ b/src/commands/SetDisplayNameCommand.ts
@@ -0,0 +1,21 @@
+import { Mjolnir } from "../Mjolnir";
+import { LogLevel, LogService } from "matrix-bot-sdk";
+
+// !draupnir displayname <displayname>
+export async function execSetDisplayNameCommand(roomId: string, event: any, mjolnir: Mjolnir, parts: string[]) {
+    const displayname = parts[2];
+
+    let targetRooms = mjolnir.protectedRoomsTracker.getProtectedRooms();
+
+    for (const targetRoomId of targetRooms) {
+        try {
+            await mjolnir.client.setDisplayName(displayname);
+        } catch (e) {
+            const message = e.message || (e.body ? e.body.error : '<no message>');
+            LogService.error("SetDisplayNameCommand", e);
+            await mjolnir.managementRoomOutput.logMessage(LogLevel.ERROR, "SetDisplayNameCommand", `Failed to set displayname to ${displayname} in ${targetRoomId}: ${message}`, targetRoomId);
+        }
+    }
+
+    await mjolnir.client.unstableApis.addReactionToEvent(roomId, event['event_id'], '✅');
+}