diff --git a/app/models/concerns/proposition_accepting.rb b/app/models/concerns/proposition_accepting.rb
new file mode 100644
index 0000000..91323e8
--- /dev/null
+++ b/app/models/concerns/proposition_accepting.rb
@@ -0,0 +1,7 @@
+module PropositionAccepting
+  extend ActiveSupport::Concern
+
+  included do
+    has_many :propositions, as: :proposition_accepting
+  end
+end