Despite the need for cognitive rehabilitation, there is a paucity of well-designed research studies to investigate treatment approaches or their effectiveness in MS. Most of published studies suffer from significant methodological flaws including small sample size, short follow-up periods, and lack of specific outcome criteria to determine improvement. O'Brien et al. (2008) recently reviewed 16 studies of cognitive rehabilitation designed to persons with MS and found only 4 class I studies and only one class I study of rehabilitation of attention deficits. Methodologically rigorous research is needed to confirm the preliminary results reported by these studies and determine the effectiveness and efficacy of cognitive rehabilitation interventions in attention deficits in MS. O'Brien et al. listed limitations found in previous studies that must be addressed in future studies. The present study was designed according to these recommendations. It is a randomized, controlled study, in parallel groups, evaluator blinded.