The ability to accurately self-assess is a critical component of professionalism and is included in the newly required Accreditation Council of Graduate Medical Education (ACGME) core competencies. To assess residents' ability to accurately self-assess their competencies related to a commonly presenting problem in geriatrics, a Standardized Patient, portraying an individual with early signs of dementia, was inserted into family medicine residents' clinic schedules. Immediately post the encounter, each resident self-assessed his/her performance using a four category (Communication, History of Present Illness, Social History, Functional Assessment), 17-item behavioral checklist. The items in each category highlighted items specific to a dementia-screening interview (e.g., HPI: Used a standardized exam which includes orientation, memory, recall and registration). Resident ratings were compared to ratings from two faculty assessors who independently viewed the videotape of each resident's SP interview. While statistically significant differences between the self-assessment and expert assessors appeared in only one of the four major check list categories (functional assessment), item specific analysis revealed significant differences on discrete items within the dementia screening interview. Implications for teaching and assessment consistent with the ACGME required competency assessment category of professionalism are discussed.