A total of 433 children, hospitalized in the Rheumatic Children's Hospital Garmisch-Partenkirchen, were followed on average for 15 years (range 10-22 years) after the onset of definite juvenile chronic arthritis. This paper reveals clearly that the different subgroups of chronic rheumatic disease in childhood with their different complications have a definite relationship to prognosis. Severe limitation with inability to attend normal school or employment occurred in 13.4% of children with systemic polyarticular arthritis (Still's syndrome) and 11.4% of the non-systemic cases, but not in the pauci-articular group. In the latter group 82.5% of the children remained without disability or with only slight impairment: this is significantly better than in the systemic or non-systemic polyarticular groups. Although the high incidence of chronic rheumatic iridocyclitis is common in children with pauci-articular arthritis, none of this group had been handicapped by severe eye complications or blindness, in contrast to several early cases with systemic or non-systemic polyarthritis. This might be due to regular eye checks in the pauci-articular group. Of the children in the systemic polyarticular group 10% were dwarfed. Mortality in the systemic group was 13.8%, in contrast to 1% in the non-systemic polyarticular and 0% in the pauci-articular arthritis group. Secondary amyloidosis was the most important cause of death, mainly in systemic cases. Of the children whose amyloidosis had been verified, 44% died in their second or third decades, mostly with uraemia.