diff --git a/gattlib-py/gattlib/exception.py b/gattlib-py/gattlib/exception.py
index d09c60b..e40affb 100644
--- a/gattlib-py/gattlib/exception.py
+++ b/gattlib-py/gattlib/exception.py
@@ -13,6 +13,8 @@
 GATTLIB_DEVICE_ERROR = 6
 GATTLIB_DEVICE_NOT_CONNECTED = 7
 GATTLIB_NO_ADAPTER = 8
+GATTLIB_BUSY = 9
+GATTLIB_UNEXPECTED = 10
 
 GATTLIB_ERROR_MODULE_MASK      = 0xF0000000
 GATTLIB_ERROR_DBUS             = 0x10000000
@@ -26,6 +28,12 @@ class GattlibException(Exception):
 class NoAdapter(GattlibException):
     pass
 
+class Busy(GattlibException):
+    pass
+
+class Unexpected(GattlibException):
+    pass
+
 class AdapterNotOpened(GattlibException):
     pass
 
@@ -84,6 +92,10 @@ def handle_return(ret):
         raise NotConnected()
     elif ret == GATTLIB_NO_ADAPTER:
         raise NoAdapter()
+    elif ret == GATTLIB_BUSY:
+        raise Busy()
+    elif ret == GATTLIB_UNEXPECTED:
+        raise Unexpected()
     elif (ret & GATTLIB_ERROR_MODULE_MASK) == GATTLIB_ERROR_DBUS:
         raise DBusError((ret >> 8) & 0xFFF, ret & 0xFFFF)
     elif ret == -22: # From '-EINVAL'
diff --git a/include/gattlib.h b/include/gattlib.h
index 0af8529..f753a4c 100644
--- a/include/gattlib.h
+++ b/include/gattlib.h
@@ -51,6 +51,7 @@ extern "C" {
 #define GATTLIB_DEVICE_NOT_CONNECTED   7
 #define GATTLIB_NO_ADAPTER             8
 #define GATTLIB_BUSY                   9
+#define GATTLIB_UNEXPECTED             10
 #define GATTLIB_ERROR_MODULE_MASK      0xF0000000
 #define GATTLIB_ERROR_DBUS             0x10000000
 #define GATTLIB_ERROR_BLUEZ            0x20000000