We report our findings in four cases of metachromatic leukodystrophy diagnosed in Greece during the last 4 years. The age of onset and the clinical symptoms were those described for the late infantile form of the disease. However, one patient retained his speech and mental abilities despite his pronounced motor regression and neurological involvement. This was combined with high residual arylsulphatase A activity in white blood cell homogenates even in the 0 degrees C incubation assay.