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Howdy, Actually, in the short-term, it may be beneficial to list both in your sitemap. The reason for this is that you want search engines to try and crawl the "old" url to process the 301 that it finds there. The quicker they visit the old URL, the faster they will realize the page is redirecting, and this actually will reduce any perceived duplicated content issues on the part of the search engines. Generally, you would do this with 2 sitemaps - one with the old URLs and one listing the new, and submit them both to Google via Webmaster Tools. You would leave the old one in place for 30 days before removing it. After 30 days, however, it's best to use a single sitemap with only one set of URLs. As Ben mentioned, you don't want search engines wasting crawling resources on forever trying to visit URLs that redirect. So after a time, it would be best to remove the old URLs from the sitemap. Unfortunately, I'm not familiar with the AceSEF Joomla package, but I believe there is a way to configure it to remove those URLs - even if manually according to the feature set: http://www.joomace.net/blog/xmap-joomap-sef-sm-2-and-acesef Hope this helps! Best of luck with your SEO.