合作社内“互联性交易”增进“联合利润”。成员间生产合作、营销合作、信用合作是增进联合利润的工具；本题借助契约理论，以“互联性交易”为分析起点，构建分析框架，试图从管理者激励和缔约条件差异两个层面解释政府推动合作社内信用合作若干年，现实“回应低迷”及存在多种合作社内信用合作治理结构的原因。.契约理论视角下，契约达成和治理结构选择由制度环境和交易特征决定。合作社内信用合作的外部金融环境、地方社会规范作为制度环境，分别及综合决定了信用合作的收益。产业门类特征、产业成熟度、管理者特质等交易特征分别及综合影响合作社内信用合作的交易费用。各因素对合作社内信用合作收益和交易费用影响的分别及综合研究，构成本课题主体研究内容。.随着上述各因素对契约达成和治理结构选择作用机理的揭示，政策制定者和实施者对合作社内信用合作的理解会更清晰，对应支持政策的“适合性”将会有提升。

Interlinked transaction enhanced combined profit of farmer specialized cooperative. Members’ cooperation on producing, marketing and credit are tools to enhance combined profit. Using contract theory, taking interlinked transaction as the precondition, this research wants to explain why most cooperative do not have credit cooperation under the condition that government encourage them to foster credit cooperation, and why there are different credit cooperative governance structure. We propose that managers’ insufficient incentive may be the main answer to the former question, and contract condition difference may be the main answer to the later question. .Contract and its governance structure are determined by institution environment and transaction character. Social norms, credit cooperation policy and finance marketing situation, as the institution environment, determine credit cooperation revenue. Industry class character, cooperation level and managers’ character, as the transaction character, determine credit cooperation transaction cost. How the above factors affect credit cooperation is the main content of this research. .If we answered the question above, policy makers and implementers would get a better understanding of credit cooperation in farmer specialized cooperative, policy would be more adaptable to reality.