Concern for equity and conservation has prompted the creation of bio-prospecting contracts for biological resources from less developed countries. One potential type of contract is between farmers who provide crop genetic resources and seed companies or agencies that use these resources. Theoretically bio-contracts will reward peasant farmers for preserving genetic resources and balance equities between farmers and seed companies. Using maize from Mexico as a case study, this paper concludes that contracting is problematic on both efficacy and equity grounds. Bio-cooperation is presented as an alternative. Institutional support and licensing agreements that support human capital development are proposed as alternatives.