Abstract: For services across the UK, increasing emphasis is placed on the use of evidence-based psychological treatments. In this context, the Scottish Government published the MATRIX, a best-practice clinical governance document, with a brief section on therapies for people with learning disabilities. As with most clinical guidelines, randomised controlled trials were considered the "gold standard." However, within the learning disability field, the existing evidence base is relatively limited, resulting in a narrow guidance for services. Methods: This study evaluated the use of best-practice guidance (the MATRIX), in a psychology service for adults with learning disabilities, covering one of the largest NHS Boards in Scotland. A randomly selected 50% (N = 73) of case notes opened since October 2011 (publication date for the MATRIX) was reviewed. Eight case notes were second-rated by an independent clinician. Results: Findings showed that service users typically presented with multiple psychological difficulties, and clinicians offered a range of therapies additional to those suggested in the guidance. This was particularly evident in cases managed by clinical psychologists. Conclusions Applying rigid therapeutic recommendations may limit opportunities for integrative practice. The potential impact of inflexibly adopting clinical guidelines on service planning and resources is discussed.