When presented with a chronic pain patient, a thorough diagnostic workup and clinical assessment are essential. A key component of this initial evaluation is to obtain the information necessary to identify the underlying cause of the pain. Although a definitive diagnosis is not always possible, pain is most effectively managed when the underlying cause is identified. Chronic pain is now viewed as a biopsychosocial phenomenon, in which biological, psychological, and social factors are at work. Although one or more chronic diseases may be responsible for at least some of the pain experienced by chronic pain patients, psychological factors also play a prominent role. According to several published reports, major depression occurs in up to 60% of chronic pain patients, and an adjustment disorder with anxious mood can be found in up to nearly a third. In addition, numerous studies have identified a high rate of substance abuse in those suffering from chronic pain, with lifetime prevalence rates ranging from 23% to 41%, according to one source. A pain history is another essential component of the initial workup. A thorough pain history includes questions on any previous therapies tried (including nonpharmacologic interventions) and the success rate of those therapies, an assessment of patient function and overall quality of life, and a review of any personal or family history of substance abuse. One of the complexities of pain diagnosis is the subjective nature of the condition. Simple validated measures, such as the 0 to 10 numerical scale, pictorial scales (eg, faces), and visual analog scales can assist in the assessment of pain intensity and the guidance of subsequent treatments. Of no less relevance in the initial workup of a patient with chronic pain is the establishment of a secure physician-patient relationship. Open and clear communication between these parties is a key component in the treatment process and will help guide the therapy more safely and efficaciously. Realistic expectations and exit strategies for each therapeutic intervention should also be discussed at the initial evaluation and again at the onset of treatment.