diff --git a/planet/spider.py b/planet/spider.py
index bbabd07..5069081 100644
--- a/planet/spider.py
+++ b/planet/spider.py
@@ -154,15 +154,28 @@ def writeCache(feed_uri, feed_info, data):
     from planet import idindex
     global index
     if index != None: index = idindex.open()
-
-    # write each entry to the cache
-    cache = config.cache_directory()
+ 
+    # select latest entry for each unique id
+    ids = {}
     for entry in data.entries:
         # generate an id, if none is present
         if not entry.has_key('id') or not entry.id:
             entry['id'] = reconstitute.id(None, entry)
             if not entry['id']: continue
 
+        # determine updated date for purposes of selection
+        updated = ''
+        if entry.has_key('published'): updated=entry.published
+        if entry.has_key('updated'):   updated=entry.updated
+
+        # if not seen or newer than last seen, select it
+        if updated >= ids.get(entry.id,('',))[0]:
+            ids[entry.id] = (updated, entry)
+
+    # write each entry to the cache
+    cache = config.cache_directory()
+    for updated, entry in ids.values():
+
         # compute cache file name based on the id
         cache_file = filename(cache, entry.id)
 
diff --git a/tests/data/spider/testfeed4.atom b/tests/data/spider/testfeed4.atom
new file mode 100644
index 0000000..0443aac
--- /dev/null
+++ b/tests/data/spider/testfeed4.atom
@@ -0,0 +1,41 @@
+<?xml version="1.0" encoding="utf-8"?>
+<feed xmlns="http://www.w3.org/2005/Atom">
+  <link rel="self" href="http://intertwingly.net/code/venus/tests/data/spider/testfeed1a.atom"/>
+  <id>tag:planet.intertwingly.net,2006:testfeed1</id>
+
+  <title>Sam Ruby</title>
+  <subtitle>It’s just data</subtitle>
+  <author>
+    <name>Sam Ruby</name>
+    <email>rubys@intertwingly.net</email>
+    <uri>http://www.intertwingly.net/blog/</uri>
+  </author>
+  <updated>2006-06-16T20:15:18-04:00</updated>
+  <link href="http://www.intertwingly.net/blog/"/>
+
+  <entry>
+    <id>tag:planet.intertwingly.net,2006:testfeed4</id>
+    <link href="http://example.com/1"/>
+    <title>Mercury</title>
+    <content>one</content>
+    <updated>2006-01-01T00:00:00Z</updated>
+  </entry>
+
+  <entry>
+    <id>tag:planet.intertwingly.net,2006:testfeed4</id>
+    <link href="http://example.com/3"/>
+    <title>Earth</title>
+    <content>three</content>
+    <updated>2006-01-03T00:00:00Z</updated>
+  </entry>
+
+  <entry>
+    <id>tag:planet.intertwingly.net,2006:testfeed4</id>
+    <link href="http://example.com/2"/>
+    <title>Venus</title>
+    <content>two</content>
+    <updated>2006-01-02T00:00:00Z</updated>
+  </entry>
+
+</feed>
+
diff --git a/tests/test_spider.py b/tests/test_spider.py
index dafbda2..9ffba8e 100644
--- a/tests/test_spider.py
+++ b/tests/test_spider.py
@@ -88,6 +88,14 @@ class SpiderTest(unittest.TestCase):
         self.spiderFeed(testfeed % '1b')
         self.verify_spiderFeed()
 
+    def test_spiderFeedUpdatedEntries(self):
+        config.load(configfile)
+        self.spiderFeed(testfeed % '4')
+        self.assertEqual(2, len(glob.glob(workdir+"/*")))
+        data = feedparser.parse(workdir + 
+            '/planet.intertwingly.net,2006,testfeed4')
+        self.assertEqual(u'three', data.entries[0].content[0].value)
+
     def verify_spiderPlanet(self):
         files = glob.glob(workdir+"/*")