diff --git a/script/remove_dup_membership.rb b/script/remove_dup_membership.rb
new file mode 100644
index 0000000..e0020f0
--- /dev/null
+++ b/script/remove_dup_membership.rb
@@ -0,0 +1,7 @@
+h = Hash.new
+Membership.find(:all).each{|membership|
+  if mem = h[[membership.person_id,membership.team_id]]
+     Membership.destroy(mem)
+  end
+  h[[membership.person_id,membership.team_id]] = membership
+}