We sought to summarize and assess original evaluations of the economic impact of clinical pharmacy services published from 1996-2000, and to provide recommendations and methodologic considerations for future research. A systematic literature search was conducted to identify articles that were then blinded and randomly assigned to reviewers who confirmed inclusion and abstracted key information. Results were compared with those of a similar review of literature published from 1988-1995. In the 59 included articles, the studies were conducted across a variety of practice sites that consisted of hospitals (52%), community pharmacies and clinics (41%), health maintenance organizations (3%), and long-term or intermediate care facilities (3%). They focused on a broad range of clinical pharmacy services such as general pharmacotherapeutic monitoring (47%), target drug programs (20%), disease management programs (10%), and patient education or cognitive services (10%). Compared with the studies of the previous review, a greater proportion of evaluations were conducted in community pharmacies or clinics, and the types of services evaluated tended to be more comprehensive rather than specialized. Articles were categorized by type of evaluation: 36% were considered outcome analyses, 24% full economic analyses, 17% outcome descriptions, 15% cost and outcome descriptions, and 8% cost analyses. Compared with the studies of the previous review, a greater proportion of studies in the current review used more rigorous study designs. Most studies reported positive financial benefits of the clinical pharmacy service evaluated. In 16 studies, a benefit:cost ratio was reported by the authors or was able to be calculated by the reviewers (these ranged from 1.7:1-17.0:1, median 4.68:1). The body of literature from this 5-year period provides continued evidence of the economic benefit of clinical pharmacy services. Although the quality of study design has improved, whenever possible, future evaluations of this type should incorporate methodologies that will further enhance the strength of evidence of this literature and the conclusions that may be drawn from it.