Practitioners have come under increasing pressure to provide objective data on assessment and treatment outcome of clients. This article provides a brief summary of assessment of eating disorders for the practicing clinician, with an emphasis on well-validated assessment instruments. The critical domains that should be covered in a thorough assessment of eating disorders are reviewed, as are some shortcomings in the current assessment literature, and also discussed is which assessment instruments for the eating disorders are most useful in a clinical context. Using well-validated, standardized assessment instruments in all phases of the treatment process is a critical part of justifying a treatment plan and providing objective data on client progress and outcome.