BACKGROUND: Psychological treatments are designed to treat pain, distress and disability, and are in common practice. No comprehensive systematic review has been published since 1999. OBJECTIVES: To evaluate the effectiveness of psychological therapies on pain, disability, and mood. SEARCH STRATEGY: Randomised controlled trials (RCTs) of psychological therapy were identified by searching MEDLINE, EMBASE and Psychlit and CENTRAL from the beginning of each abstracting service until January 2008. A further search was undertaken from January 2008 to August 2008. Additional studies were identified from the reference lists of retrieved papers and from discussion with investigators. SELECTION CRITERIA: Full publications of RCTs of psychological treatments compared with an active treatment, waiting list or treatment as usual. Studies were excluded if the pain was primarily headache, or was associated with a malignant disease. Studies were also excluded if the number of patients in any treatment arm was less than 10. DATA COLLECTION AND ANALYSIS: Fifty-two studies were examined with a quality rating scale specifically designed for use with these studies. Data were extracted from 40 studies (4781 participants) by two authors. Two main classes of treatment (Cognitive Behavioural Therapy (CBT) and Behaviour Therapy (BT)), were compared with two control conditions (Treatment as Usual (TAU) and Active control (AC)), at two assessment points (immediately following treatment and six months following treatment), giving eight comparisons. For each comparison, treatment effectiveness was assessed on three outcomes: pain, disability, and mood giving a total of 24 analyses. MAIN RESULTS: Overall there is an absence of evidence for BT, except for pain immediately following treatment compared with TAU. CBT has some small positive effects for pain, disability and mood. At present there is insufficient data on quality or content of treatment to investigate their influence on outcome. The quality of the trial design has improved over time but the quality of treatments has not. AUTHORS' CONCLUSIONS: CBT and BT have weak effects in improving pain. CBT and BT have minimal effects on disability associated with chronic pain. CBT and BT are effective in altering mood outcomes, and there is some evidence that these changes are maintained at six months.