diff --git a/gnuviechadmin/osusers/admin.py b/gnuviechadmin/osusers/admin.py
index e5d0448..e0e9adc 100644
--- a/gnuviechadmin/osusers/admin.py
+++ b/gnuviechadmin/osusers/admin.py
@@ -14,10 +14,13 @@ class AdditionalGroupInline(admin.TabularInline):
 
 class ShadowInline(admin.TabularInline):
     model = Shadow
+    readonly_fields = ['passwd']
+    can_delete = False
 
 
 class UserAdmin(admin.ModelAdmin):
     inlines = [AdditionalGroupInline, ShadowInline]
+    readonly_fields = ['uid']
 
 
 admin.site.register(Group)