Subcutaneous protein C concentrate (Immuno, Vienna) was used to treat a child with homozygous protein C deficiency who was formerly treated with intravenous protein C concentrate. After 3000 units subcutaneous protein C concentrate (250 iu/kg), protective protein C levels were maintained for 48 h after infusion, with peak levels at 12 h. Subcutaneous protein C concentrate is given every third day and is well tolerated by the patient. No thrombotic events have occurred. We conclude that subcutaneous administration of protein C concentrate is a valuable therapeutic option in the long-term management of homozygous protein C deficiency and avoids the potential hazards of long-term central venous lines.