Organizations play key roles in modern societies. The importance of organizations for a society requires an understanding of organizations. In order to fully understand public organizations, it is necessary to recognize how organizational settings affect subjects of organizations and organizing. Although public and private organizations interrelate with each other, the two types are not identical. In this dissertation, I attempt to describe public organizations in their own setting by discussing three important topics in public organization theory: (1) innovation adoption in the public sector; (2) representative bureaucracy; and (3) decline and death of public organizations. In Chapter II, I scrutinize early adoption of innovations at the organizational level and explore which public organizations become early adopters in the diffusion process. The adoption of an innovation is directly related to the motivation to innovate. That is, organizations performing poorly will have a motivation to seek new solutions. I estimate the strength of the motivation by observing prior performance. The main finding of the second chapter is that performance-based motivation has a twofold impact on early innovation adoption: negative for organizations with low performance, but positive for those with very high performance. This study estimates top 3.8% as the turning point defining which organizations attain outstanding performance and show the positive relationship between performance and innovation adoption. In Chapter III, develop a theoretical framework for predicting and explaining active representation in bureaucracy and test two hypotheses from the framework to test its validity. First, active representation requires the loss of organizational rewards. Second, a minority group mobilizes external support to minimize the cost of active representation. These findings support that active representation is a political activity in which bargaining between formal and informal roles occurs. In addition, I add evidence to the literature demonstrating that the two prerequisites – policy discretion and a critical mass – must be satisfied for active representation to occur. In Chapter IV, I argue that organizational change is a result of a relationship between an organization and the environment. And, I suggest and advance the theory of organizational ecology for examining environment effect on organizational decline and death. The theory has been extensively studies in the business sector, so I advance the theory to be applicable to the public sector. First, I add political variables, such as change in the executive branch and the legislature, unified government, and hypothesize that (1) an organization established by a party other than the one in the executive branch in any given year will be more likely to be terminated or decline; that (2) an organization established by a party other than the one in the legislature in any given year will be more likely to be terminated or decline; and that (3) if an unfriendly party controls both the executive branch and the legislature, organizations established by other parties are more likely to be terminated or decline. Second, the effect of the economic environment on the life cycle of public organizations is not as straightforward and simple as their effect on business firms.