Nine cases of progressive pseudorheumatoid chondrodysplasia in subjects aged 7-60 years are reported. Six of them were members of one large family with several consanguineous marriages. Evaluation of six generations of this family suggested an autosomal recessive mode of inheritance. The presentation of the disease was between the ages of 3 and 8 years with waddling gait and fusiform swelling of the interphalangeal joints of the hands, clinically resembling juvenile rheumatoid arthritis. Most of the other joints become progressively involved, with crippling disability. One of the patients had typical features of Blount disease at presentation.