OBJECTIVE: To summarise the state of knowledge in terms of economic impact of rheumatoid arthritis (RA), to highlight the level of aggregation of categories of costs in different economic evaluations and to identify the burden of productivity costs in RA. METHODS: Several computerised databases (Medline, Embase, Econlit, OHE HEED, NHS EED) were searched to identify the relevant studies for the review. Among the hundreds of records found, 18 were selected for the analysis. The majority of them were cost of illness studies. At the first stage three main categories of costs were considered (medical direct costs, non-medical direct costs, productivity costs) and the economic impact of each category was quantified. Then subcategories of costs were investigated in order to assess the grade of homogeneity in the level of aggregation among different studies. RESULTS: Direct medical costs were included in every study. Total average direct medical costs were in the range of US$6000 per year (per patient). Among them, hospital costs constituted in general the largest amount (from 25 to 40%), followed by medications and arthritis professional visits. There was considerable lack of homogeneity in the assessment of cost categories. Many studies showed a skewed distribution of costs among patients in relation to their level of severity. Non-medical direct costs were in general not substantial. By contrast the economic impact of indirect costs has resulted extremely high, ranging from 1 to 3-4 times the direct costs. Productivity costs are likely to be underestimated given the difficulty of assessing the costs associated with premature mortality. CONCLUSION: The literature review indicated a strong need for a standardisation in the assessment of relevant costs for RA. Although there were differences in the level of aggregation, all studies reported productivity costs to be the largest category. New drugs with the ability to reduce the long-term consequences of RA are likely to have a significant economic impact.