Twenty-five central venous lines (two external 23 subcutaneous ports) were placed in 19 boys with haemophilia A (n = 17) or B (n = 2). The mean age of the boys was 4.9 years (range 0.2-15.3 years). The haemophilia was severe (factor level < 1%) in 18 boys and moderate (factor level 3%) in one. Three boys had circulating inhibitors and three were positive for human immunodeficiency virus (HIV)-1 antibody. Central venous lines were placed to facilitate intermittent factor replacement therapy (n = 6), long-term factor prophylaxis (n = 9), induction of an immune tolerance protocol (n = 2) or therapy for acquired immunodeficiency syndrome (AIDS)-related complications (n = 2). The ports remained in place for 15795 days (mean 687 days, range 11-2059 days). The frequency of port-related sepsis was 48% (11/23 ports in eight boys) or 0.7 port infections per 1000 patient days. Ports were removed from five boys with an unresolved infection (four with Staphylococcus aureus sepsis and one with Pseudomonas sp. sepsis). Other complications requiring port removal included a catheter tip placed too high in the venous system (n = 1), severe persistent pain associated with needle access of the port (n = 1) and a subclavian vein thrombosis (n = 1). Both the benefits and risks of a subcutaneous port should be considered when deciding whether to place this device in a very young child with haemophilia.