This paper portrays the development of a concession-investment optimization model for optimizing the winning potential of a concession-bid from the prospective promoters' viewpoints by taking into account imprecise investment parameters. A financial performance measure has been developed to quantify bid-winning potential. Fuzzy set theory is embedded into a genetic algorithm to optimize bid-winning prospects of concession schemes under uncertainty. The fuzzy vertex method accomplishes propagation of uncertainty in cash flows arising from imprecision in estimation of investment parameters. Genetic algorithm solves the optimization routine. The developed model yields global near-optimal solution of bid-winning potential with contributing values of concessionary items: concession length, base price, and equity level under uncertain investment environment. A numerical example demonstrates model capabilities. The model results would help promoters devise a profitable, yet competitive, financial proposal.