From a consecutive series of 3,847 headache patients, 1,331 patients who made first visits for new headache to 120 primary care physicians were studied for usual care over a 14-month period. Either tension or vascular headache was the initial diagnosis in 23.8 percent and 12.8 percent of patients, respectively. Nearly one half (47.8 percent) were classified as having headaches other than tension or vascular. A total of 15.3 percent of headaches were undiagnosed or were regarded as a mixture of traditional diagnostic designations. At first visit, most patients (76.6 percent) were managed without diagnostic tests. Drugs were prescribed for 73.6 percent, and advice was given for 58.6 percent. Only 2.0 percent of patients had computerized tomographic scanning ordered at first visit, although at least 46 percent met National Institutes of Health criteria, a finding with potential economic consequences of at least $2 billion. These findings suggest the need for reevaluation of diagnostic categories for headache, reevaluation of strategies for headache management, and further investigations of headache in primary care patients.