It is widely believed that patients' reluctance to report pain and adhere to treatment recommendations are significant barriers to cancer pain control. However, few investigators have examined barriers to cancer pain management from the cancer patient's perspective. Ambulatory patients with cancer who had experienced cancer-related pain in the previous month or were currently taking analgesics for cancer pain control were asked to participate in this study. Information regarding (a) pain assessment, (b) pain medication use, (c) concerns and barriers to compliance, (d) communication patterns regarding pain and pain control, and (e) demographics were collected during a 10-min structured interview. Approximately 20% of patients with a current cancer diagnosis who were approached reported that they had experienced pain or taken analgesic drugs during the preceding month. Eighty-eight percent of these patients ranked their pain as five or greater (scale, 0-10), and 81% reported impaired function due to pain. Major barriers to effective treatment included forgetfulness, the belief that pain should be tolerated, concerns about side effects, and fear and disdain of dependence, addiction, and tolerance. One-third of patients felt that their pain could not be better controlled than it currently was. Patients reported frequent communication regarding pain and pain control with physicians (52%), nurses (41%), and pharmacists (17%). The low pain prevalence, coupled with high pain intensity and associated dysfunction, appears to be a reflection of patient's unwillingness to report pain of mild to moderate intensity. In addition to previously recognized factors, stoicism and fatalism represent significant barriers to cancer pain control.