This study examines how national UK newspaper websites are integrating user-generated content (UGC). A survey quantifying the adoption of UGC by mainstream news organisations showed a dramatic increase in the opportunities for contributions from readers. In-depth interviews with senior news executives revealed this expansion is taking place despite residual doubts about the editorial and commercial value of material from the public. The study identified a shift towards the use of moderation due to editors' persistent concerns about reputation, trust, and legal liabilities, indicating that UK newspaper websites are adopting a traditional gate-keeping role towards UGC. The findings suggest a gate-keeping approach may offer a model for the integration of UGC, with professional news organisations providing editorial structures to bring different voices into their news reporting, filtering and aggregating UGC in ways they believe to be useful and valuable to their audience. While this research looked at UGC initiatives in the context of the UK newspaper industry, it has broad relevance as professional journalists tend to share a similar set of norms. The British experience offers valuable lessons for news executives making their first forays into this area and for academics studying the field of participatory journalism.