Previous research on colorectal cancer patients has suggested that considerable delay can occur once the patient has sought medical care. However, little information has been available on the possible components of this delay. In this study, detailed information on diagnostic delays was collected from 294 symptomatic patients. Of these patients, 46% reported experiencing at least one delay. Three types of diagnostic delay were identified and were associated with different lengths of delay. Of all the delays, 31% were due to difficulties in scheduling initial or subsequent office visits or laboratory tests; these were associated with an average delay of 3 weeks. Physician-related delays (e.g., misdiagnosis or observation of symptoms without specific action) comprised 46% of all diagnostic delays and resulted in an average delay of 18 weeks. The remainder of the delays were patient-related and resulted in an average delay of 12 weeks. There was no association between any of these three delay types, suggesting that attempts to reduce diagnostic delay should encompass all three types in order to be maximally effective.