BACKGROUND:Impairments in cognitive function, particularly memory, are common in patients with Multiple Sclerosis (MS) and these can potentially affect their ability to complete functional activities. There is evidence from single-case or small group studies that memory rehabilitation can be beneficial for patients with MS but findings from randomised controlled trials (RCTs) and systematic reviews have been inconclusive. OBJECTIVES:To determine the effectiveness of memory rehabilitation for patients with MS who have memory problems, and the effect of such interventions on functional abilities. SEARCH METHODS:We searched the Cochrane Multiple Sclerosis Group's Specialised Trials Register (last searched February 2011), and the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, latest issue), NIHR Clinical Research Network database, MEDLINE (1966 to February 2011), EMBASE (1980 to February 2011), CINAHL (1982 to April 2010), PsycINFO (1980 to February 2011), AMED (1985 to April 2010), British Nursing Index (1985 to April 2010) and CAB Abstracts (1973 to April 2010). We handsearched relevant journals and reference lists. SELECTION CRITERIA:We selected RCTs of memory rehabilitation or cognitive rehabilitation for patients with MS in which a memory rehabilitation treatment group was compared to a control group. Selection was conducted independently first and confirmed through group discussion. Studies that included participants whose memory deficits were the result of conditions other than MS were excluded unless a subgroup of participants with MS with separate results could be identified. DATA COLLECTION AND ANALYSIS:Four reviewers were involved in study selection, quality assessment and data extraction. Investigators of primary studies were contacted for further information where required. Data analysis and synthesis were conducted in accordance with the Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 [updated March 2011]. A 'best evidence' synthesis was performed based on the methodological quality of the primary studies included. MAIN RESULTS:Eight studies, involving 521 participants, were included. The interventions involved various memory retraining techniques, such as computerised programmes and training on internal and external memory aids. Control groups varied in format from assessment-only groups, discussion and games, non-specific cognitive retraining and attention or visuospatial training. The risk of bias of the included studies was generally low; three of the studies were evaluated to have high risk of bias related to certain aspects of their methodology. Meta-analysis showed no significant effects of memory rehabilitation on memory function or functional abilities immediately or long-term. No significant effect of intervention was found, either immediately or long-term, on subjective reports of memory problems [Standard mean difference (SMD) 0.06 (95% confidence interval [CI] -0.21 to 0.34) and SMD 0.04 (95% CI -0.24 to 0.31)] respectively; on objective memory [SMD 0.24 (95% CI -0.02 to 0.49) and SMD 0.19 (95% CI -0.09 to 0.47)]; on mood [SMD -0.04 (95% CI -0.26 to 0.17) and SMD 0.13 (95% CI -0.10 to 0.36)]; and on Quality of Life [SMD -0.13 (95% CI -0.12 to 0.39) and SMD -0.11 (95% CI -0.39 to 0.17)]. On Activities of Daily Living, no immediate treatment effect was observed [SMD -0.13 (95% CI -0.60 to 0.33)], but on long-term follow up the intervention group performed significantly worse than the control group [SMD -0.33 (95% CI -0.63 to -0.03)]. AUTHORS' CONCLUSIONS:There is no evidence to support the effectiveness of memory rehabilitation on memory function or functional abilities in patients with MS. However, this conclusion has been arrived because of the limited quality of some of the primary studies reviewed in this area. Further robust, RCTs of higher methodological quality and better quality of reporting are needed.