The aim of our study was to evaluate the changes of hemodialysis (HD) service and main demographic characteristics of HD patients in Lithuania during seven years period. From 1996 to 2003 we visited annually all HD centers in Lithuania and collected data about all HD patients. There was a sharp increase in the number of HD centers (from 17 to 37), HD stations (from 25 p. m. p. (per million population) to 87 p.m.p.; p<0.001), HD patients (from 60 p.m.p. to 264 p.m.p.; p<0.001) and incidence of new HD patients (from 54.3 p.m.p. to 92 p.m.p.; p<0.01). In 1996 all 17 HD centers in Lithuania were public. Private HD centers appeared in 1998 and reached 43.2% of all HD centers (n=16) in 2003. 44.8% of HD patients were dialyzed in private HD centers. The mean age of HD patients increased from 47.2+/-16.1 years in 1996 to 57.5+/-14.9 years in 2003 (p<0.001). HD population became older. The percentage of patients over 60 years old increased from 22.8% to 49.7% (p<0.001) and over 70 years old--from 54% to 21.9% (p<0.001). The main underlying disease of end-stage renal disease was chronic glomerulonephritis but its rate had decreased from 54.5% in 1996 to 26.5% in 2003 (p<0.001). During this period there was a statistically significant increase in the incidence of end-stage renal disease due to diabetics (from 7.1% to 18.0%; p<0.01), hypertensive nephropathy (from 3.1% to 9.4%; p<0.05), and chronic pyelonephritis (from 11.2% to 18.6%; p<0.01). In summary during the last seven years HD service in Lithuania expanded significantly, and rapid development of private HD was observed. The number of HD patients was rising continuously with predominance of diabetic, hypertensive and elderly patients.