Nine NHS walk-in centre pilot sites opened in London during 2000. Six of the nine centres are located in hospital sites. The other three centres are in Soho in central London, the High Street in Croydon, and Parsons Green in Fulham. NHS walk-in centres are nurse-led and offer primary care services without an appointment. All nine centres offer assessment and treatment for minor illnesses and minor injuries and advice and information about other services. Additional services offered vary by walk-in centre. This project provides a snapshot of how NHS walk-in centres are developing in London. The data were collected between February and April 2001. The focus of this study is on staffing issues, such as recruitment, training and developing the nursing role, and the interaction with other services. Face-to-face interviews were conducted with a range of walk-in centre staff and other local stakeholders from primary care and accident and emergency (A&E) departments. [Executive summary abbreviated]