diff --git a/rcon/__init__.py b/rcon/__init__.py
index 821f1a1..c5a9591 100644
--- a/rcon/__init__.py
+++ b/rcon/__init__.py
@@ -1,7 +1,8 @@
 """RCON client library."""
 
 from rcon.asyncio import rcon
+from rcon.exceptions import RequestIdMismatch, WrongPassword
 from rcon.proto import Client
 
 
-__all__ = ['Client', 'rcon']
+__all__ = ['RequestIdMismatch', 'WrongPassword', 'Client', 'rcon']
diff --git a/rcon/asyncio.py b/rcon/asyncio.py
index f182d0c..46fc496 100644
--- a/rcon/asyncio.py
+++ b/rcon/asyncio.py
@@ -3,6 +3,7 @@
 from asyncio import open_connection
 from typing import IO
 
+from rcon.exceptions import RequestIdMismatch, WrongPassword
 from rcon.proto import Packet
 
 
@@ -26,12 +27,12 @@ async def rcon(command: str, *arguments: str, host: str, port: int,
     response = await communicate(reader, writer, login)
 
     if response.id == -1:
-        raise RuntimeError('Wrong password.')
+        raise WrongPassword()
 
     request = Packet.make_command(command, *arguments)
     response = await communicate(reader, writer, request)
 
     if response.id != request.id:
-        raise RuntimeError('Request ID mismatch.')
+        raise RequestIdMismatch(request.id, response.id)
 
     return response.payload
diff --git a/rcon/console.py b/rcon/console.py
index 00a1352..dd2552e 100644
--- a/rcon/console.py
+++ b/rcon/console.py
@@ -3,6 +3,7 @@
 from getpass import getpass
 
 from rcon.config import Config
+from rcon.exceptions import RequestIdMismatch, WrongPassword
 from rcon.proto import Client
 
 
@@ -80,8 +81,8 @@ def login(client: Client, passwd: str) -> str:
     while True:
         try:
             client.login(passwd)
-        except RuntimeError as error:
-            print(error)
+        except WrongPassword:
+            print('Wrong password.')
             passwd = read_passwd()
             continue
 
@@ -110,7 +111,7 @@ def process_input(client: Client, passwd: str, prompt: str) -> bool:
 
     try:
         result = client.run(command, *args)
-    except RuntimeError:
+    except RequestIdMismatch:
         print(MSG_SESSION_TIMEOUT)
 
         try:
diff --git a/rcon/errorhandler.py b/rcon/errorhandler.py
index 0acc04a..034c514 100644
--- a/rcon/errorhandler.py
+++ b/rcon/errorhandler.py
@@ -4,6 +4,8 @@ from logging import Logger
 from socket import timeout
 from sys import exit    # pylint: disable=W0622
 
+from rcon.exceptions import RequestIdMismatch, WrongPassword
+
 
 __all__ = ['ErrorHandler']
 
@@ -30,6 +32,10 @@ class ErrorHandler:
             self.logger.error('Connection timed out.')
             exit(4)
 
-        if isinstance(value, RuntimeError):
-            self.logger.error(str(value))
+        if isinstance(value, WrongPassword):
+            self.logger.error('Wrong password.')
+            exit(5)
+
+        if isinstance(value, RequestIdMismatch):
+            self.logger.error('Session timed out.')
             exit(5)
diff --git a/rcon/exceptions.py b/rcon/exceptions.py
new file mode 100644
index 0000000..d8407b0
--- /dev/null
+++ b/rcon/exceptions.py
@@ -0,0 +1,17 @@
+"""RCON exceptions."""
+
+__all__ = ['RequestIdMismatch', 'WrongPassword']
+
+
+class RequestIdMismatch(Exception):
+    """Indicates a mismatch in request IDs."""
+
+    def __init__(self, sent: int, received: int):
+        """Sets the sent and received IDs."""
+        super().__init__()
+        self.sent = sent
+        self.received = received
+
+
+class WrongPassword(Exception):
+    """Indicates a wrong password."""
diff --git a/rcon/gui.py b/rcon/gui.py
index 0d2269e..91ad850 100644
--- a/rcon/gui.py
+++ b/rcon/gui.py
@@ -14,6 +14,7 @@ require_version('Gtk', '3.0')
 from gi.repository import Gtk
 
 from rcon.config import LOG_FORMAT
+from rcon.exceptions import RequestIdMismatch, WrongPassword
 from rcon.proto import Client
 
 
@@ -207,8 +208,12 @@ class GUI(Gtk.Window):  # pylint: disable=R0902
             self.show_error('Connection refused.')
         except (TimeoutError, timeout):
             self.show_error('Connection timed out.')
-        except RuntimeError as error:
-            self.show_error(str(error))
+        except WrongPassword:
+            self.show_error('Wrong password.')
+        except RequestIdMismatch as mismatch:
+            self.show_error(
+                'Request ID mismatch.\n'
+                f'Expected {mismatch.sent}, but got {mismatch.received}.')
         else:
             self.result_text = result
 
diff --git a/rcon/proto.py b/rcon/proto.py
index fa7a158..ca11711 100644
--- a/rcon/proto.py
+++ b/rcon/proto.py
@@ -7,6 +7,8 @@ from random import randint
 from socket import SOCK_STREAM, socket
 from typing import IO, NamedTuple, Optional
 
+from rcon.exceptions import RequestIdMismatch, WrongPassword
+
 
 __all__ = [
     'LittleEndianSignedInt32',
@@ -200,7 +202,7 @@ class Client:
         response = self.communicate(Packet.make_login(passwd))
 
         if response.id == -1:
-            raise RuntimeError('Wrong password.')
+            raise WrongPassword()
 
         return True
 
@@ -213,6 +215,6 @@ class Client:
             if self.passwd is not None and self.login(self.passwd):
                 return self.run(command, *arguments)
 
-            raise RuntimeError('Request ID mismatch.')
+            raise RequestIdMismatch(request.id, response.id)
 
         return response if raw else response.payload