Group B streptococcus is the most common cause of neonatal sepsis in the United States of America (USA). This study was undertaken to determine the contribution of group B streptococcus to neonatal septicaemia in Antigua and Barbuda. From 1994 to 2002, there were about 12,000 births, with 2500 Special Care Nursery admissions, 1100 (44%) with potential neonatal septicaemia. Blood cultures were done in 433/1100 (39%) and cerebrospinal fluid cultures in 52/1100 (5%). Positive cultures were seen in 41/433 (9.5%) with group B streptococcus in 1/41 (2.4%), streptococcus "species" in 3/41 (7.4%) and positive cerebrospinal fluid cultures were seen in 2/52 (one group B streptococcus) giving 5 per 12,000 or 0.4 cases per 1000 babies. Vaginal cultures from 1994 to 2002 revealed group B streptococcus in 14/163 (8.6%) of positive bacterial cultures. A sample of pregnant women from a private office had positive culture for group B streptococcus in 2/120 (1.7%). The prevalence rate of carriage (15 to 40%) and infection (1.7 to 4 per 1000 babies) was much higher in the USA in the same period Universal screening of mothers for group B streptococcus may not be as necessary or cost-effective in Antigua and Barbuda.