The paper presents the epidemiology and socio-economic aspects of the three most common rheumatic diseases: rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and scleroderma. The incidence of rheumatic diseases in a population is estimated at 4–5%. Prevalence rate for RA in Poland is 0.45% of the adult population and is similar to the rate reported in the EU (0.49%). It is estimated that the average incidence of SLE is 40–55 per 100 thousand and that the annual incidence of systemic sclerosis is 19–35 cases per million (depending on the country). Nearly 18% of all hospital admissions in Poland are associated with rheumatic diseases. The introduction of new classification criteria for rheumatoid arthritis, allowing classification of the early forms of the disease and their use in clinical practice will probably change the assessment of incidence of this disease in the population.