「平行外交」是1980年代以來新興出現的專有名詞，其意味著中央政府與次國家政府之間可能因為各種因素導致不同外交政策的出現。筆者以魁北克的經驗為例，探討次國家政府發展外交關係的背景、動機以及最終獲致的成效如何。筆者結合了平行外交的相關理論、魁北克的歷史、魁北克發展外交的進程、魁北克現行的外交關係網絡，以及加拿大聯邦政府的反應，歸納出對於上述提及問題的各個觀點，最終呼應至論文題目「平行外交的概念與應用」。 / “Paradiplomacy” is a specialized term which appeared since 1980, it means different foreign policy could happen between central government and sub-national government due to any kinds of causes. Take Quebec’s experience as example, the author wants to analyze that how a sub-national government has gone under such context, also included his motives and the effects of paradiplomacy. The author will end up a conclusion of this article “the Concept and Application of Paradiplomacy” in terms of the comprehensive understanding of the theories of paradiplomacy, the history of Quebec, the progress of Quebec’s foreign policy, the contemporary diplomatic networks of Quebec, and the response from the federal government of Canada.