We assess the knowledge available on the difficulties experienced by multiple sclerosis (MS) patients in work-related activities. A literature review was carried out using the keywords 'multiple sclerosis' and 'employment' or 'work' through PubMed and EMBASE. Papers reporting patient-derived data on difficulties at work as primary or secondary outcome measures and published in the period 2002-December 2011 were searched. A total of 26 papers were selected, for a total of 32 507 patients (mean age 46.2 years; 42.1% with relapsing-remitting MS). Most papers reported observational studies or cross-sectional surveys focused on health-related quality of life and MS costs. Symptoms more frequently addressed are fatigue, mobility and cognitive impairments. Limited research has been carried out on the working environment. We found a relatively small number of papers published in the last 10 years on the difficulties that patients with MS can experience at work, and this kind of information always appeared as a secondary outcome. In general, it is possible to affirm that MS has a strong impact on patients' employment status, as the mean unemployment rate was 59%. Research on factors promoting maintenance of remunerative employment is required.