Abstract: | Homework or between‐session learning has long been considered an essential aspect of effective cognitive behaviour therapy. However, it has received relatively less empirical attention than other components of cognitive behaviour therapy. In general, studies have found that homework completion is predictive of outcome in psychotherapy. However, the amount of homework completed by a patient represents only one aspect of this important therapeutic component. This study investigated both the quantity and the quality of homework completed during a 10‐week group cognitive and behavioural treatment program for anxious and depressed patients. It explored the relationship between various aspects of homework completion and outcomes on several different variables. A total of 94 patients were included in the analysis. It was found that both quantity and quality of homework completed predicted outcome on measures of depression, anxiety and quality of life at post‐treatment and at 1‐month follow‐up. The results were strongest for the amount of homework completed, suggesting that clinicians should encourage patients to complete homework even if the homework content is not entirely accurate. The results of this study highlight the importance of homework as a central part of effective cognitive and behavioural treatment. |