There is an increasing focus on disease control programs in developing countries such as Thailand and a growing use of techniques of economic analysis to assist in optimal policy on disease- control. In Thailand, while national vaccination programs have been applied, maintenance of disease free zones in the south and central regions is becoming an increasingly important objective given recent changes in international trade protocol. While several economic assessment techniques can be applied to evaluate disease control programs (Murphy 1996b), this paper will provides a simple bio-economic model that integrates deterministic epidemiological modelling with economic optimising techniques. The model attempts to highlight important economic considerations in the optimal control of FMD within a zoning framework. However as outlined in Murphy (1996b), while this approach provides a useful conceptual framework for determining optimal economic conditions, it is limited in its direct application particularly to national control programs. It is in this framework that cost-benefit approaches, despite their inability to provide essentially optimal solutions, are better able to attribute values to such factors as shadow prices and incorporate the distributional welfare issues associated with national control programs.