Internal organ function, biochemical, and immunological variables were assessed in 100 patients with progressive systemic sclerosis (PSS), 37 with diffuse scleroderma and 63 with the CREST syndrome. The frequency of oesophageal symptoms and dysmotility did not differ between the two subsets, but patients with diffuse scleroderma had more pronounced motility disturbances. Calcinosis, Raynaud's phenomenon, and telangiectasia were equally frequent in the two groups. Vital capacity, total lung capacity, and static lung compliance were lower among patients with diffuse scleroderma (p less than 0.001), who also had a higher frequency of lung fibrosis (p less than 0.001) and cardiomegaly (p less than 0.01). Sixty eight per cent of the patients with diffuse scleroderma and 62% of those with the CREST syndrome had a positive antinuclear antibody test, which was associated with oesophageal hypomotility (p less than 0.001), fat malabsorption (p less than 0.01) and pulmonary dysfunction (p less than 0.05). Thus, the severity of organ manifestations varied not only with the form of PSS, but also with the absence/presence of antinuclear antibody. This study shows that the term 'CREST syndrome' could be replaced by 'limited cutaneous systemic sclerosis'.