自2000 年後日本對亞太區域經濟整合與締結雙邊自由貿易協定日趨熱 衷。2013 年日本正式加入由美國主導之跨太平洋夥伴協定（TPP），象徵著 其參與區域經濟整合的高峰。本文之目的在探討自2000 年代後期以來，日 本對區域經濟整合的思維與政策發展，並以日本加入TPP 的政策制定過程為 例，剖析日本政府是如何克服國內的疑慮與反對而加入此一區域自貿協定。 本文採質化研究途徑，透過訪談日本官員、利益團體與學者及分析相關文 獻，以了解日本加入TPP 政策的制定過程。本文研究發現，日本在TPP 政 策制定過程中逐漸顯現從原先日本民主黨強調以政治家主導政策方向、領導 官僚，回復到自民黨執政後由政治家匯集政治支持，而仰賴官僚輔佐之決策 作成的發展趨勢。

Since 2000, Japan has become more active in signing free trade agreements（FTA）and regional economic integration. Japan’s decision to join the Trans-Pacific Partnership（TPP）in 2013 has reached an apex of its efforts in engaging in regional integration. The goal of this paper is to explore Japan’s FTA policy and its evolution by focusing on Japan’s decision to join the TPP. This paper adopts a qualitative approach by interviewing Japanese officials, scholars, interest groups and mass media to investigate Japan’s TPP policy-making process. The results suggest that during the TPP policy development, politicians collecting political support and bureaucrats providing professional expertise have become the most noticeable features in the policy-making process.