diff --git a/progit/lib.py b/progit/lib.py
index 9064987..0cc8372 100644
--- a/progit/lib.py
+++ b/progit/lib.py
@@ -82,7 +82,7 @@ def new_project(session, user, name, folder,
 
 
 def list_projects(
-        session, username=None,
+        session, username=None, fork=None,
         start=None, limit=None, count=False):
     '''List existing projects
     '''
@@ -93,6 +93,16 @@ def list_projects(
             user=username
         )
 
+    if fork is not None:
+        if fork is True:
+            projects = projects.filter(
+                model.Project.parent_id != None
+            )
+        elif fork is False:
+            projects = projects.filter_by(
+                parent_id = None
+            )
+
     if start is not None:
         projects = projects.offset(start)