追求美好的生活，過著幸福美滿的日子，一直是人類社會戮力以赴的目標。自良古以來，人類就不斷嘗試各種制度途徑，以求能夠找出一個最能實趁此目標的答案。本文首先論析Michael Walzer的「公民社會概念」，Walzer 指出，古典的公民積極參與政治、馬克斯主張的合作式經濟、資本主義強調的自由放任式經濟，以及民族主義主張的歷史與血緣關係，四項解答各有可取之處，但卻附隨更多的缺失，因此皆非追求美好生活的良方！Walzer認為只有強調社團生活的公民社會，使其與國家、市場、社區等部門有一緊密的串連而成為多樣化與多元化，才是較佳的處方。 接著本文第二部分引申公民社會的核心概念分析第三部門的特質，以及第三部門與其他三個部門之間的互動關係。作者強調目前學術或實務界慣用的「非營利」 (non-profit) 或「非政府」(non-government) 來統稱該類型組織， 不免拘泥於組織或部門間界線 (boundary) 的區分而無法真正體會該類型組織與國家、市場及社區與家庭問互動的彈性空間，以及對於公民社會建構所產生的影響。未來在台灣社會，如何以第三部門為主的社團生活方式融入政治、經濟、社會、文化性質的組織裡，使之多樣性與多元化，將是吾人可以持續觀察的一項議題；而學術界對台灣第三部門領域的研究，也應跳脫組織或部門之間界線嚴格區分的思維，著力於探討該類型組織與國家、市場、社區與家庭問互動的利基及其所產生的問題。

The pursuit of the preferred setting, the most supportive environment, and sorts of institutions for the good life is the ever goal that human being make great efforts try to achieve. To provide answers to make this dream come true, human being have tried various approaches and institutions since the beginning of history. The first part of this paper present a detailed discussion of the "concept of civil Society" elaborated originally by Michael Walzer (1995).Walzer emphasized that there are four rival ideologies, including political community, Marx's cooperative economy, the Capitalist definition of the marketplace, and the nationalist stand by ties of blood and history. Each has its own claim to completeness and correctness. However, each neglects the necessary pluralism of any civil society. Walzer offered a fifth answer, holding that the good life can only be lived in civil society in which people freely associate and communicate with one another, form and reform groups of all sorts, not for the sake of any particular formation but for the sake of sociability itself. Walzer pointed out that the quality of our political and economic activity and of our national culture is intimately connected to the strength and vitality of our associations. Extending the meaning of the Walzer's concept of civil society, the second part of this paper discusses the characteristics of the third sector and the relations between the third sector and other sectors. The author of this paper emphasizes that it is inappropriate for academics and practitioners at present to use the term of "nonprofit" or "nongovernmental" consistently in describing the kind of organizations of the third sector. The conventional usage of the term described above is easy to push itself into dire straits because of the view that a clear boundary among sectors is necessary. Furthermore, this proposition tends to ignore the resilience of interaction among NPOs/NGOs, state, market, and community, and will produce negative impacts on the construction of civil society. Finally, reflections on the relations among the third sector, the public sector, and the private for-profit sector are presented.