The efficacy of a newly designed syringe prepacked with human diploid cell vaccine in a sufficient quantity to deliver individual 0.1 ml doses intradermally was tested by injecting 40 veterinary students with a single dose on each of days 0, 7 and 28. A second group of 20 students received the ordinary series of three 1.0 ml intramuscular vaccine doses by needle and syringe. All participants in both groups developed neutralizing antibodies to rabies above the suggested minimum of 0.5 international units per ml by day 49. The geometric mean titres were somewhat lower in the group receiving the 0.1 ml doses compared to the group given 1.0 ml doses; however, this was considered of no clinical significance since everyone achieved a titre above the suggested minimum. There was little difficulty in reconstituting the vaccine prepacked in the lumen of the syringe and the syringe was easy to manipulate.