diff --git a/agent/crawl/base.py b/agent/crawl/base.py
index baa7944..0902484 100644
--- a/agent/crawl/base.py
+++ b/agent/crawl/base.py
@@ -49,4 +49,10 @@ class Metadata(object):
     def __init__(self, data=dict()):
         self.data = data
 
+    def asXml(self):
+        # TODO...
+        return ''
+
+    def set(self, key, value):
+        self.data['key'] = value
 
diff --git a/agent/crawl/filesystem.py b/agent/crawl/filesystem.py
index 0b4b6f1..c1dcab6 100644
--- a/agent/crawl/filesystem.py
+++ b/agent/crawl/filesystem.py
@@ -36,15 +36,14 @@ from loops.agent.crawl.base import Metadata
 class CrawlingJob(BaseCrawlingJob):
 
     def collect(self):
-        self.data = []
-        #deferred = reactor.deferToThread(self.crawlFilesystem, dataAvailable)
-        deferred = self.deferred = Deferred()
-        self.internalDeferred = coiterate(self.crawlFilesystem())
-        self.internalDeferred.addCallback(self.finished)
-        return deferred
+        self.collected = []
+        coiterate(self.crawlFilesystem()).addCallback(self.finished)
+        # TODO: addErrback()
+        self.deferred = Deferred()
+        return self.deferred
 
     def finished(self, result):
-        self.deferred.callback(self.data)
+        self.deferred.callback(self.collected)
 
     def crawlFilesystem(self):
         criteria = self.params
@@ -59,8 +58,11 @@ class CrawlingJob(BaseCrawlingJob):
                     mtime = datetime.fromtimestamp(
                                 os.stat(filename)[stat.ST_MTIME])
                     # TODO: check modification time
-                    self.data.append((FileResource(filename),
-                                      Metadata(dict())))
+                    meta = dict(
+                        path=filename,
+                    )
+                    self.collected.append((FileResource(filename),
+                                           Metadata(meta)))
                     yield None
 
 
diff --git a/agent/crawl/filesystem.txt b/agent/crawl/filesystem.txt
index e569a03..26a63b9 100644
--- a/agent/crawl/filesystem.txt
+++ b/agent/crawl/filesystem.txt
@@ -35,6 +35,8 @@ We are now ready to schedule the job and let the reactor execute it.
   >>> scheduler.schedule(crawlJob, int(time()))
 
   >>> tester.iterate()
+  Metadata: {'path': '...data...file1.txt'}
   Transferring: Data from file1.txt
+  Metadata: {'path': '...data...subdir...file2.txt'}
   Transferring: Data from file2.txt
 
diff --git a/agent/interfaces.py b/agent/interfaces.py
index 7c30acf..44798bf 100644
--- a/agent/interfaces.py
+++ b/agent/interfaces.py
@@ -124,7 +124,7 @@ class IMetadataSet(Interface):
             (nested metadata) this will be converted to XML as well.
         """
 
-    def setData(key, value):
+    def set(key, value):
         """ Set a metadata element.
 
             The value may be a string or another metadata set
diff --git a/agent/testing/crawl.py b/agent/testing/crawl.py
index 110f3ef..52929a8 100644
--- a/agent/testing/crawl.py
+++ b/agent/testing/crawl.py
@@ -26,7 +26,7 @@ from twisted.internet import reactor
 from twisted.internet.defer import Deferred
 from zope.interface import implements
 
-from loops.agent.interfaces import ICrawlingJob, IResource, IMetadataSet
+from loops.agent.interfaces import ICrawlingJob, IResource
 from loops.agent.crawl.base import CrawlingJob as BaseCrawlingJob
 
 
@@ -39,12 +39,7 @@ class CrawlingJob(BaseCrawlingJob):
         return deferred
 
     def dataAvailable(self):
-        self.deferred.callback([(DummyResource(), Metadata())])
-
-
-class Metadata(object):
-
-    implements(IMetadataSet)
+        self.deferred.callback([(DummyResource(), None)])
 
 
 class DummyResource(object):
diff --git a/agent/testing/transport.py b/agent/testing/transport.py
index ae1dad4..d755546 100644
--- a/agent/testing/transport.py
+++ b/agent/testing/transport.py
@@ -55,6 +55,8 @@ class Transporter(BaseTransporter):
             data.close()
         else:
             text = data
+        if metadata is not None:
+            print 'Metadata:', metadata.data
         print 'Transferring:', text
         return Deferred()