Using data from the 1973 American Hospital Association national survey of hospital medical staff organization, six factors of medical staff organization structure are examined in relation to each other and to hospital ownership, size, teaching status, geographic region and size of Standard Metropolitan Statistical Area (SMSA). The six factors include 1) Resource Capability; 2) Generalist Physician Contractual Orientation; 3) Communication and Control; 4) Local Staff Orientation; 5) Physician Participation in Decision Making; and 6) Hospital-Based Contractual Orientation. Several relatively distinct patterns emerged related to hospital ownership, size, teaching activity and region of the country, as well as interrelationships among the factors themselves. Differences between smaller and larger hospitals clearly emerged as well as a distinctive pattern for for-profit hospitals. All of the factors are subject to manipulation through administrative and/or public policy interventions and the findings suggest dimensions for future investigation of important policy issues related to the medical staff's role in cost containment, utilization, quality assurance and technology adoption.