Public policy design is a progressive process that needs constant amendment. According to the progressive decision-making theory of Lindblom，all public policies need to be progressively debugged. Powerful public policies，in particular，should strike a balance between value and means and seek changes while safeguarding stability，thereby exploring a set of optimized public policies. In addition，public policy design should transform the traditional ideas，evolve from one-way procedural policy design into result-oriented design，fully consider the needs of policy objects and constantly amend and improve existing policies. Policy design mainly researches practical problems that can be solved by public policies while policy amendment aims to improve policy quality. This paper selects policy adjustment of Shanghai Community Affairs Service Center as a case study and introduces the progressive decision-making theory to analyze optimization of public policy design，coordination between policy subjects and objects and process optimization of public policy implementation.