政务服务“跨省通办、省内通办” 是一项在深化政府职能转变、服务区域一体化发展和人口流动新趋势，及适应新冠疫情防控“三态叠加”背景下，破除由户籍辖地管理所致的政务服务碎片化的创新举措。本文对话地方政府间合作文献，吸收工具性和合法性维度的影响因素，构建“跨域通办”“需求侧-供给侧”整合性解释框架，聚焦中国长三角、珠三角及其毗邻省份，包含155个地级行政区样本和11935个非定向“城市对”，创新式地从合作决策的三个层面剖析府际合作的生成逻辑——合作广度、合作联结和合作程度。定量分析识别了合作决策三层面的动力机制及其差异。地方政府间合作广度的促进因素包括社会需求和组织需求；合作联结的促进因素包括社会需求、区域需求、组织需求和财政供给；而合作程度的促进因素只有组织需求。面对“解决流动人口异地办事难”这一核心政策目标，社会需求只对合作广度和合作联结起正向促进作用，对合作程度无相关作用。面对“服务两市间宏观合作”这一次要政策目标，区域需求只对合作联结起正向促进作用，对合作广度和合作程度均无相关作用。而组织需求对合作联结、合作广度和合作程度均起正向促进作用。地方政府在合作多维度决策中，选择性地在某些维度考虑社会需求，而在另一些维度忽略。通过过程追踪揭示三层面动力机制差异化的根本原因。合作广度和联结层面存在较大宣传象征性和考核可能性，倒逼城市在决策时关注社会需求。而合作程度直接决定执行成本，且考核可能性较低。社会需求（流动人口规模）在合作程度层面转化为执行成本（跨域服务规模），因此流动人口规模不再起正向推进作用。更深层次分析可知，上级考核体系衍生了“留痕”业务和“孔洞”业务，基层执行体系在上级盲区内做成本理性选择，最终呈现对合作不同层面的差异化执行——在选择签约对象和规划签约数量时，考虑社会需求；在决策事项数量时，不考虑社会需求。本该环环相扣的三个层面出现了割裂，导致最终呈现的合作效果流于形式。本文为首次探究我国政务服务“跨省通办、省内通办”实践背后复杂机制的混合型研究，识别城市在不同合作层面的动力和阻力，为纵深推进通办合作提供有益的政策启示。本文创新提出的合作决策三层面模型、“需求侧-供给侧”框架、授权型非毗邻合作模式及个别变量的测量方法可有效补充府际合作研究。

Delivering government services on a cross-city basis is an innovative initiative to break down the fragmentation of government services caused by the local management of household registration, in the context of the “triple overlap” refers to deepening the transformation of government functions, serving the new trend of integrated regional development and population mobility, and adapting to the control of the COVID-19 epidemic. The expansion of the geographical scope and range of services covered by it is an important task in building a service-oriented government that satisfies the people. This new type of delegated authority cooperation in non-adjacent areas has not yet been discussed in depth by academics.The study observed a sample of 155 inter-local government services cooperation across 11 provinces in southeast China, which are 11935 undirected dyads. Based on the literature on inter-local cooperation, this paper constructs an integrated explanatory framework of "Needs - Supply" by incorporating two dimensions of influence, namely, instrumentality and legitimacy, analyzes the formation logic of inter-local cooperation from three perspectives of cooperative decision-making: cooperation breadth, cooperation connection and cooperation degree. The quantitative analysis identifies the different motivational mechanisms behind the three perspectives of cooperation decision making. The factors that promote the cooperation include social needs and organization needs; the promoting factors of cooperation connection include social needs, region needs, organization needs and financial supply; the only factor promoting the degree of cooperation is organization needs. That is to say, in view of the core policy target of "solving the difficulties for the migrants", social needs only positively promote the cooperation breadth and cooperation connection, but have no significant effect on the cooperation degree. For the secondary policy target of "serving the macro-strategic cooperation between the two cities", region needs only plays a positive role in promoting the cooperative connection, but has no significant effect on the breadth and degree of cooperation. Organization needs has a positive effect on cooperative breadth, connection and degree.The qualitative analysis reveals the underlying reasons for the different mechanisms behind the three perspectives. Both cooperation breadth and city dyads‘ cooperative connection have the symbolic meaning of publicity and higher likelihood of being assessed, which forcing cities to focus on instrumentality and legitimacy needs when making decisions. The degree of cooperation determines the implement cost and has lower likelihood to be assessed. The size of the migrants, which is both the social needs and the cost, it doesn’t play a positive propulsive role for the degree perspective. The superior assessment system produced "mark" and "hole" types. The grassroots implementation system made rational cost decisions in the superior blind area, and then presented differentiated implementation of different levels of cooperation — considering the needs of the migrant population when selecting partners and determining cooperation quantity. When determining the quantity of government services, the social needs is not considered.This study is the first time to explore the complex mechanisms behind the practice of Delivering government services on a cross-city basis in China, identify the dynamics and difficulties of cities at different perspectives of cooperation, and provide policy insights for the deepening of services cooperation. At the same time, the three-perspectives model of cooperation, the " Needs - Supply" framework and the classic type of delegated not-adjacent cooperation can effectively complement the study of inter-local cooperation.