An information synthesis was conducted to examine nurse practitioner effectiveness as substantiated in existing literature. After an extensive computerized and manual search of the literature, 248 documents judged by staff to be relevant to the topic were reviewed by a content-area expert (N = 11 members), and a methodology expert (N = 8 members). Experts had been chosen on the basis of multiple nominations from an extensive national survey of professional nurses in leadership positions. Upon completing the respective reviews, experts identified key areas in support of NP effectiveness that had not been established or clarified in existing literature. A summary and discussion of the experts' recommendations for future studies in support of nurse practitioner effectiveness are presented.