Book excerpt: Occupational therapists are expected to maintain their knowledge of best practice by independently keeping up to date on the latest research. With this work, the authors have assembled the evidence for effectiveness of occupational therapy for adults and older adults. It brings together the latest published peer-reviewed literature, conceptual approaches, outcome measures, and intervention approaches to address the three main areas by: Identifying a finite set of interventions which occupational therapists deliver most often, and providing details of those intervention approaches; Identifying where the research evidence shows that occupational therapists can achieve specific positive effects as a result of those interventions; Identifying the outcome measures most commonly and reliably used by researchers in occupational therapy to demonstrate the effects of interventions. The authors have comprehensively reviewed all of the intervention effectiveness literature for occupational therapy provided for adults. The material reviewed crosses all diagnostic categories and areas of practice for adults and older adults. Analysis of over 500 research studies and systematic reviews form the basis for this book.