A large family with adrenoleukodystrophy is described and the case histories of two clinically symptomatic and related male patients are presented. Clinical, biochemical and genetic screening of their family demonstrated two clinically affected males, one biochemically affected male and five carrier females. Two women were symptomatic; one suffered an acute exacerbation. One female was diagnosed as a carrier, based on genetic analysis and the family history only. Endocrinological screening was performed in the five affected males, demonstrating an elevated adrenocorticotrophic hormone level and a normal cortisol level in two, as evidence of compensated adrenocortical failure.