In February 1999, the Accreditation Council for Graduate Medical Education (ACGME) identified six general competencies as the basic educational goals required by all training programs for their residents. This places emphasis on educational outcome assessment in residency programs and in the accreditation process. A concomitant goal is to have increasingly valid, reliable assessments of the ability of a resident physician to provide safe, evidenced-based, humanistic medical care to their patients. To better define these competencies for the specialty of emergency medicine (EM), the Council of Emergency Medicine Residency Directors (CORD-EM) held a consensus conference in March 2002. This article reports the results of the Consensus Group for the core competency area of medical knowledge. This competency is already being well addressed in residency programs, but there has been inadequate documentation of a resident's knowledge base. The Consensus Group focused on many assessment methods to determine those having the best potential for use in EM programs. Assessment methods felt to be most appropriate for assessment of the medical knowledge base of a resident are presented, as are practical suggestions for incorporating these into EM programs.