diff --git a/modules/services/x11/display-managers/kdm.nix b/modules/services/x11/display-managers/kdm.nix
index d0d30effbf0..55ab406b9e9 100644
--- a/modules/services/x11/display-managers/kdm.nix
+++ b/modules/services/x11/display-managers/kdm.nix
@@ -22,6 +22,8 @@ let
 
       [X-:*-Core]
       ServerCmd=${dmcfg.xserverBin} ${dmcfg.xserverArgs}
+      # Needed to prevent the X server from dying on logout and not coming back:
+      TerminateServer=true
 
       [X-*-Greeter]
       HiddenUsers=root,nixbld1,nixbld2,nixbld3,nixbld4,nixbld5,nixbld6,nixbld7,nixbld8,nixbld9,nixbld10