The workshop on Internet-based Groupware for User Participation in Product Development (IGROUP) was held on November 14, 1998, in conjunction with the conferences CSCW 98 and PDC 98 in Seattle, WA, USA. The workshop gathered 16 participants from both academia and industry. The topic discussed was how we can use groupware technology to involve end-users in the development of software and non-software products.The context for product development has traditionally been separated from the users' work context (Grudin 1991). In a product development process the user group is often unknown. Products are often purchased off-the-shelf, and the developers can in most cases only guess which user community and what types of users will be using their products. The only source of user feedback in these situations is from laboratory experiments with "typical users," and in some occasions from product resellers. The result is often sub-optimal solutions.In the recent years this picture has changed drastically. Technical innovations, in particular the Internet, have made it possible to bring closer together product developers and end-users. In its beginning, the developers started using a "feedback button" as a menu choice in their programs. Pushing this button would let the user compose a "complaint" message and send it to the developer. Lately, more advanced methods have emerged, trying to construct mixed communities of end-users and developers, where one of the aims is to deliver products users really want.In this workshop, we took a look at how groupware is or could be used to facilitate collaboration between users and developers in order to increase the quality of the product. Ten position papers discussed different aspects of user involvement using groupware technology. In this report we will first give a summary of the position papers and then discuss the areas that we saw as important for further investigation.