search from AgEcon., American Agricultural Economics Association Annual Meeting, August 2-5, 1998, Salt Lake City, Utah. 1998 18 p., To justify public subsidies for export promotion, export markets must fail to provide incentives for exporters to recognize the benefits of spillover or long-term benefits of promotion. This paper tests for these failures in dynamic dual model for horticultural export supply. Results show significant spillovers and dynamic effects.