在公私合夥潮流下，我國於2001年制定「促進民間參與公共建 設法」，本著「政府最大的審慎」及「民間最大的參與」，將公共 建設由政府委託民間投資廠商興建與營運，以提供民眾使用。在此 種代理關係中，公部門係以公共利益爲政策規劃目標，而私部門則 以營利爲目標，所以適宜採經濟分析方法評估BOT法制。尤其在 BOT模式中，固然政府已提供用地取得、特許經營權、附屬事業及 融資與租稅優惠等誘因機制，但對於公共工程之營建品質、工期及 收費取價，乃至營運服務品質皆設有監督管理機制；而BOT投資契 約則是規範公部門與私部門權利義務之依據。本文即以代理理論之 視角，分析促參法及BOT投資契約之代理假設、代理風險、代理成 本及資訊不對稱問題。即以經濟學分析BOT公共建設之法制，以確 立公、私部門在BOT模式中的角色扮演，也爲促參法之公私合夥推 動公共建設法制提出經濟性分析，以提供未來訂立BOT投資契約內容之參考。

Following the trend of public-private partnership (PPP), the “Encouragement for Private Participation in Infrastructure Projects Act” was passed in February 2001 in Taiwan. Based on the principles of most prudence of government and most participation of private sector, the public construction are commissioned by government, and built and operated by private investor to provide for public use. In this agency relationship, the government plans for public interest, while the private business works for profits. For this reason, it is ideal to evaluate BOT legal regime by economic analysis. Though the government has provided eminent domain, franchise, financing, tax reduction and other incentive mechanism in BOT model, the scheduling of construction, pricing and quality of the service in operation stage are supervised by government. The BOT investment contract is the basis of rights and duties between the public and private sector. This paper is to, from agency theory, evaluate the issues of agency assumption, agency risk, agency cost and information unsymmetrical of PPP model and BOT investment contract. Economic analysis of law is very useful in the disputes settlement of BOT investment contract, and it will clarify the role of public and private sectors in PPP. It will be an ideal reference to amend BOT law and draft BOT contract.