In this paper, our aim is to facilitate synchronous and co-present interaction with social bookmarking systems for groups of related users meeting to discuss and share their collections of tags and bookmarks. Our work results in a system called Orchis that proposes a graphical user interface based on cooperative visualization and interaction as an alternative graphical user interface for social bookmarking systems. Orchis presents three major characteristics: (1) graphical overviews of collections of annotated bookmarks and tags, (2) advanced drag-and-drop interaction styles adaptable to distributed display environments and (3) support for distributed architectures possibly running different windowing systems. Our hypothesis is that by using Orchis, related users will be able to better compare and share tags and bookmarks. They will also be able to build cooperatively valuable shared collections. We expect that, in turn, this will participate in improving the overall quality of both folksonomies and social bookmarking collections.