Zotero 1.5 (www.zotero.org) has been released in public beta. Users can now access their Zotero collections from anywhere and synchronize them across multiple machines (of any operating system). Zotero is a free, easy-to-use Firefox extension to help users collect, manage, and cite research sources. It requires the new Firefox 3.0. Zotero 1.5 also offers significant performance improvements over Zotero 1.0.