The prevalence of brucellosis among abattoir workers in Saudi Arabia was determined through a randomised multi-stage sampling of 1200 abattoir workers. Diagnosis was made by both blood culture and standard tube agglutination test. The overall prevalence of brucellosis was 4.0% among abattoir workers. Infection was more common among butchers (8.9%), veterinarians and veterinary assistants (5.4%), and administrative personnel (1.1%). In order to reach optimum planning for a national brucellosis control programme in Saudi Arabia, ministerial co-ordination should be established with formulation of inter-governmental veterinary agreements between the Saudi government and the relevant authorities of animal exporting countries. A national survey on animal marketing is required.