diff --git a/tailbone/forms2/core.py b/tailbone/forms2/core.py
index c1cf9782..3dcd46e3 100644
--- a/tailbone/forms2/core.py
+++ b/tailbone/forms2/core.py
@@ -177,8 +177,8 @@ class Form(object):
     """
 
     def __init__(self, fields=None, schema=None, request=None, readonly=False, readonly_fields=[],
-                 model_instance=None, model_class=None, nodes={}, enums={}, labels={}, renderers={}, widgets={},
-                 action_url=None, cancel_url=None):
+                 model_instance=None, model_class=None, nodes={}, enums={}, labels={}, renderers={},
+                 widgets={}, defaults={}, action_url=None, cancel_url=None):
 
         self.fields = list(fields) if fields is not None else None
         self.schema = schema
@@ -196,6 +196,7 @@ class Form(object):
         self.labels = labels or {}
         self.renderers = renderers or {}
         self.widgets = widgets or {}
+        self.defaults = defaults or {}
         self.action_url = action_url
         self.cancel_url = cancel_url
 
@@ -265,6 +266,11 @@ class Form(object):
                 if key in schema:
                     schema[key].widget = widget
 
+            # apply any default values
+            for key, default in self.defaults.items():
+                if key in schema:
+                    schema[key].default = default
+
             self.schema = schema
 
         return self.schema
@@ -330,7 +336,7 @@ class Form(object):
         """
         Set the default value for a given field.
         """
-        raise NotImplementedError # TODO
+        self.defaults[key] = value
 
     def render(self, template=None, **kwargs):
         if not template: