Physicians' professionalism and humanism have become central foci of the efforts of medical educators as the public, various accrediting and licensing agencies, and the profession itself have expressed concerns about the apparent erosion of physicians' competency in these aspects of the art, rather than the science, of medicine. Of the many obstacles to enhancing trainees' skills in these domains, one of the most significant is the difficulty in assessing competency in physicians' professionalism and humanism. The author suggests that the assessment of these aspects of the art of medicine has more in common with the approaches used in criticism of the arts than with the quantitative assessment tools appropriate to the scientific method and the medical model. Quantitative and semi-quantitative tools, so effective in elucidating the etiology, pathophysiology, and treatment of disease, are often in-appropriate and invalid when applied to evaluation of professional and humanistic competencies. The author proposes that humanism "connoisseurs" be employed to qualitatively evaluate medical trainees' professionalism and humanism. Such connoisseurs would possess expert knowledge, training, and experience in the interpersonal aspects of the art of medicine, allowing them to deconstruct concepts such as empathy, compassion, integrity, and respect into their respective key elements while evaluating physicians' behaviors as an integrated, cohesive whole. Through the use of a rich descriptive vocabulary, humanism connoisseurs would provide valid formative and summative feedback regarding competency in medical professionalism and humanism. In the process, they would serve to counteract the relative marginalization of professionalism and humanism in the informal and lived curricula of medical trainees.