diff --git a/setup.cfg b/setup.cfg
index a5da691..056f833 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -21,6 +21,7 @@ packages = find:
 python_requires = >=3.8
 install_requires =
     click
+    qrcode
     deltachat
 
 [options.packages.find]
diff --git a/src/teams_bot/bot.py b/src/teams_bot/bot.py
new file mode 100644
index 0000000..a5c50fd
--- /dev/null
+++ b/src/teams_bot/bot.py
@@ -0,0 +1,73 @@
+import logging
+from threading import Event
+
+import deltachat
+from deltachat import account_hookimpl
+
+
+class SetupPlugin:
+    def __init__(self, admingrpid):
+        self.member_added = Event()
+        self.admingrpid = admingrpid
+        self.message_sent = Event()
+        self.outgoing_messages = 0
+
+    @account_hookimpl
+    def ac_member_added(self, chat: deltachat.Chat, contact, actor, message):
+        if chat.id == self.admingrpid and chat.num_contacts() == 2:
+            self.member_added.set()
+
+    @account_hookimpl
+    def ac_message_delivered(self, message: deltachat.Message):
+        if not message.is_system_message():
+            self.outgoing_messages -= 1
+            if self.outgoing_messages < 1:
+                self.message_sent.set()
+
+
+def get_crew_id(ac: deltachat.Account, setupplugin: SetupPlugin = None) -> int:
+    """Get the group ID of the crew group if it exists; warn old crews if they might still believe they are the crew.
+
+    :param ac: the account object of the bot.
+    :param setupplugin: only if this function is run during `teams-bot init`.
+    :return: the chat ID of the crew group, if there is none, return 0.
+    """
+    crew_id = 0
+    for chat in reversed(ac.get_chats()):
+        if (
+            chat.is_protected()
+            and chat.num_contacts() > 1
+            and chat.get_name() == f"Team: {ac.get_config('addr')}"
+        ):
+            logging.debug(
+                "Chat with ID %s and title %s could be a crew", chat.id, chat.get_name()
+            )
+            if crew_id > 0:
+                old_crew = ac.get_chat_by_id(crew_id)
+                old_crew.set_name(f"Old Team: {ac.get_config('addr')}")
+                new_crew = [contact.addr for contact in chat.get_contacts()]
+                new_crew_emails = " or ".join(new_crew)
+                quit_message = f"There is a new Group for the Team now; you can ask {new_crew_emails} to add you to it."
+                logging.debug(
+                    "Sending quit message to old crew with ID %s: %s",
+                    old_crew.id,
+                    quit_message,
+                )
+                old_crew.send_text(quit_message)
+                if setupplugin:
+                    setupplugin.outgoing_messages += 1
+                old_crew.remove_contact(ac.get_self_contact())
+            crew_id = chat.id
+        else:
+            logging.debug(
+                "Chat with ID %s and title %s is not a crew.", chat.id, chat.get_name()
+            )
+    if crew_id:
+        crew_members = [
+            contact.addr for contact in ac.get_chat_by_id(crew_id).get_contacts()
+        ]
+        crew_emails = " or ".join(crew_members)
+        logging.debug("The current crew has ID %s and members %s", crew_id, crew_emails)
+    else:
+        logging.debug("Currently there is no crew")
+    return crew_id
diff --git a/src/teams_bot/cli.py b/src/teams_bot/cli.py
index 3a55a80..8aa8f2c 100644
--- a/src/teams_bot/cli.py
+++ b/src/teams_bot/cli.py
@@ -1,5 +1,11 @@
-import click
 import logging
+import sys
+
+import click
+import qrcode
+import deltachat
+
+from .bot import SetupPlugin, get_crew_id
 
 
 def set_log_level(verbose: int, db: str):
@@ -41,6 +47,60 @@ def init(ctx, email: str, password: str, db: str, verbose: int):
     """Configure bot; create crew; add user to crew by scanning a QR code."""
     set_log_level(verbose, db)
 
+    ac = deltachat.Account(db)
+    ac.run_account(addr=email, password=password, show_ffi=verbose)
+    ac.set_config("mvbox_move", "1")
+    ac.set_config("sentbox_watch", "0")
+
+    crew_id_old = get_crew_id(ac)
+
+    chat = ac.create_group_chat(
+        "Team: {}".format(ac.get_config("addr")), contacts=[], verified=True
+    )
+
+    setupplugin = SetupPlugin(chat.id)
+    ac.add_account_plugin(setupplugin)
+
+    chatinvite = chat.get_join_qr()
+    qr = qrcode.QRCode()
+    qr.add_data(chatinvite)
+    print(
+        "\nPlease scan this qr code with Delta Chat to join the verified crew group:\n\n"
+    )
+    qr.print_ascii(invert=True)
+    print(
+        "\nAlternatively, copy-paste this invite to your Delta Chat desktop client:",
+        chatinvite,
+    )
+
+    print("\nWaiting until you join the chat")
+    sys.stdout.flush()  # flush stdout to actually show the messages above
+    setupplugin.member_added.wait()
+    setupplugin.message_sent.clear()
+
+    chat.send_text(
+        "Welcome to the %s crew! Type /help to see the existing commands."
+        % (ac.get_config("addr"),)
+    )
+    print("Welcome message sent.")
+    setupplugin.message_sent.wait()
+
+    if crew_id_old:
+        setupplugin.message_sent.clear()
+        try:
+            new_crew_id = get_crew_id(
+                ac, setupplugin
+            )  # notify old crew about who created the new crew
+            assert (
+                new_crew_id == chat.id
+            ), f"Bot found different 'new crew' than the one we just created; consider deleting {db}"
+            setupplugin.message_sent.wait()
+        except ValueError as e:
+            logging.warning("Could not notify the old crew: %s", str(e))
+        print("The old crew was deactivated.")
+    sys.stdout.flush()  # flush stdout to actually show the messages above
+    ac.shutdown()
+
 
 @teams_bot.command()
 @click.option(