We propose and evaluate QuWi (Quality in Wikipedia), a framework for quality control in Wikipedia. We build upon a previous proposal by Mizzaro [11], who proposed a method for substituting and/or complementing peer review in scholarly publishing. Since articles in Wikipedia are never finished, and their authors change continuously, we define a modified algorithm that takes into account the different domain, with particular attention to the fact that authors contribute identifiable pieces of information that can be further modified by other authors. The algorithm assigns quality scores to articles and contributors. The scores assigned to articles can be used, e.g., to let the reader understand how reliable are the articles he or she is looking at, or to help contributors in identifying low quality articles to be enhanced. The scores assigned to users measure the average quality of their contributions to Wikipedia and can be used, e.g., for conflict resolution policies based on the qual...