The increasing complexity of hospitals and the emergence of corporate responsibility calls for greater trust amongst the Board, Administration and Medical Staff. Physicians will play a more important role in the hospital decision-making process. Boards will expect the medical staff organization to better define and monitor processes for physician credentialling, evaluation, peer review and discipline. Because these issues are complex and sensitive, only the organized medical staff can appropriately address them. Clarification of roles and responsibilities of the President of the Medical Staff, the Chief of Staff and the medically qualified administrative officer is crucial in the development of appropriate relationships and processes.