The Dr. Martin Luther King, Jr., Health Center has developed a simple inexpensive McBee Card Surveillance System for following approximately 2,000 registered patients with hypertension. The system has been in use for the past two years by three health teams. On a quarterly basis teams and physicians are given reports on the percentage of their hypertensive patients with controlled blood pressure (bp) (bp less than or equal to 140/90 for patients younger than 50; bp less than or equal to 160/95 for 50 or older). In addition, patients not seen in the past 4 months are identified for follow-up by family health workers. During the 2-year period that the system has been in operation, the three teams have increased their percentage of patients under control by 50%. Of 929 patients with hypertension, 411 were controlled at the inception of the study and 617 were controlled 2 years later. Such a simple surveillance and self-evaluaton system is readily applicable to all ambulatory care settings.