Can J Psychiatry 2008;53(8):485^86 Substance use problems and chronic nonmalignant pain are 2 major causes of human suffering, health care use, and psychiatric and psychosocial dysfunction in the United States and around the world. Point prevalence estimates of chronic pain in the United States range from about 10% to 50% of the population, depending on the several definitions used,1 with similar rates reported elsewhere in the world.2 Even higher rates of chronic pain are reported in individuals with opioid and other substance use disorders,3 and rates of substance use problems both in the United States and in Canada are highly prevalent and growing.4-5 Substance use disorders and chronic pain produce an impressive and strikingly similar range and number of negative effects on humans and society, and cause notable concerns and dilemma in health care workers and across the entire health care treatment system. At a basic level, both problems are strong motivators of human behaviour, much of which is maladaptive. Substance use and chronic pain problems are commonly associated with high rates of health care use and hospitalization, and pain is the most common complaint given by individuals seeking health care in the United States.6 Substance use disorder also provokes a wide range of illegal and socially maladaptive behaviours to sustain access to drugs and to help disguise some of the negative effects of these substances on mood and behaviour.7 Another striking similarity between substance use and chronic pain problems is their blindness to social class and economics. These problems affect poor and wealthy alike, ignore educational background and accomplishments, and are oblivious to intelligence and talent. Equally important, each of these problems is related to marked deterioration in psychiatric and psychosocial functioning,7-8 including high rates of persistent unemployment.9-10 Other noteworthy similarities is their strong relation to increase risks of other health care problems, their ability to confound the diagnostic and treatment process of other psychiatric and medical disorders, and their capacity to create notably strained relations between patients and health care providers. Most of these problems are amplified in individuals unfortunate enough to have both substance use disorder and chronic pain. The articles in this In Review address these problems by focusing on 2 unique subgroups of patients that experience similar clinical courses and overall problem profiles. The article by Dr Michael Kidorf and Dr Van L King11 focus on a subset of injection drug users participating in a community-based syringe exchange program (SEP) to reduce the risk of human immunodeficiency virus and other blood-borne dis ease transmission. The report authored by Dr Michael R Clark, Dr Kenneth B Stoller, and me12 focuses on a subset of chronic pain patients enrolled in an outpatient treatment program for opioid and other substance dependence disorders. Both articles provide a clear and disturbing picture of the scope and severity of problems experienced by these individuals and the disturbingly low numbers of them receiving any specific treatment for their many problems. Despite the somewhat daunting scope of these problems, each article provides a rational and empirically based set of evaluation and treatment guidelines that have a good chance to improve access to treatment and overall quality of care. The article by Dr Kidorf and Dr King11 provides a comprehensive overview of the growth and benefits of community SEPs over the past decade, a compelling characterization of the scope and severity of drug use and other problems in injection drug users, and illustrates the large mismatch between these problems and the near absence of any treatment for them. A clear case and lucid strategy is presented for efforts to expand the benefits of community-based SEPs by using these settings to engage and motivate syringe exchangers to seek substance abuse treatment. …