The W-QLI index was field tested for clients and providers by using local mental health providers known to the authors. Results of the initial validation work have been reported in detail elsewhere.(1) In order to ensure content and face validity of the W-QLI, we based the conceptual framework and the development of the instrument on a comprehensive model of QoL that includes multiple dimensions as well as multiple perspectives on the client's QoL. Furthermore, both consumers and professionals considered to have expertise and extensive experience with persons suffering from severe and persistent mental illness were involved in the development, definition and choice of items and/or scales to be included to represent these multiple dimensions of life quality. Finally, to the extent possible, existing valid scales were chosen to capture some aspects of the various domains and dimensions of QoL.