近年来，政府面临的治理问题的复杂程度不断提升，例如环境保护、应急管理、贫困帮扶等问题往往都需要多部门、跨越行政边界合作才能完成，这对传统官僚体制中清晰政府职能和边界的设计提出了诸多挑战。协同治理是近期政府部门为了完成复杂公共事物治理而尝试的新兴治理模式。在协同治理形成过程中，有些机制设计依赖于横向的协同主体自愿推动形成、而有些则依赖于自上而下的纵向干预。但是鲜有研究能够勾勒清楚纵向干预与横向要素间的关系，以及二者对协同治理形成的影响路径。借助京津冀大气污染联防联控的实践样本，本研究聚焦以下具体研究问题：1）上级政府所使用的不同类型的纵向干预手段分别对协同治理的形成存在怎样的影响？2）不同纵向干预手段与协同主体间的横向要素如何互动、以及如何交互影响协同治理的形成？ 本研究基于京津冀区域长期以来已经使用过的纵向干预手段的文本分析结果，将纵向干预总结为明确参与范围、明确参与目标、规定协同机制、规定问责机制、提供资源支持五种手段，并分别讨论五种手段以及手段之间的组合，与横向的内部协商、内部合法性以及内部领导力产生了怎样的互动，进而共同作用于协同治理结果。综合运用定性和定量混合研究方法，本文深入探究了纵向干预对协同治理的影响机制。研究过程中，通过构建2006-2021年京津冀区域地方政府间大气污染联防联控数据库，运用逻辑回归、结构方程模型、定性比较分析方法以及案例研究分析方法，本文发现：第一，内部动机是协同主体间形成协同治理的本质原因。其次，纵向干预会通过内部动机间接对协同治理产生影响，其中，明确参与范围的干预手段会通过削弱内部协商机制降低协同治理产生的概率，规定协同机制和规定问责机制则会通过增强内部合法性增加协同治理产生的概率。最后，上级政府面向存在权力不对称性的地方政府，使用特定的纵向干预组合能够导致协同治理结果。 本项研究一方面从理论上丰富了对协同治理和纵向干预的讨论，建构了纵向干预与横向要素之间的复杂逻辑关系，并系统性还原了协同治理的形成过程。另一方面，本项研究结论在中国政策语境下，为上级政府选择纵向干预工具实现协同活动或协同治理目标提供了政策建议。

With the increasing complexity of governance issues facing the government in recent years, multiple-department collaboration across administrative boundaries is required to tackle such problems as environmental protection, emergency management, and poverty alleviation. This type of collaboration poses enormous challenges to clearly defining government functions and boundaries in traditional bureaucracy system. Collaborative governance is a recently emerging governance model proposed by the government attempting to govern the complex commons. In the formation of collaborative governance, some mechanisms are designed based on the voluntary promotion of horizontal collaborators, while others are generated by top-down hierarchical interventions. However, few studies have clarified the relationship between hierarchical interventions and horizontal elements, and the pathways through which they influence the formation of collaborative governance.In this paper, a practice sample of joint air pollution prevention and control in the Beijing-Tianjin-Hebei area was examined to figure out three problems. What influence do different hierarchical interventions have on the formation of collaborative governance? How do different hierarchical interventions interact with horizontal elements between collaborators? How do the interactions between hierarchical interventions and horizontal elements affect the formation of collaborative governance?In this study, research results of hierarchical interventions that had long been applied in the Beijing-Tianjin-Hebei region were analyzed. There were five hierarchical interventions studied, including defining the participation scope, clarifying the participation goal, formulating collaboration and accountability mechanisms, and providing resource support. How each of the five means and their combinations interact with the horizontal internal negotiations, legitimacy, and leadership was discussed. Moreover, what effects did the interactions had on collaborative governance formation were explored. Mixed qualitative and quantitative research methods were adopted in this paper to delve into the mechanisms of the influence of hierarchical interventions on collaborative governance. A database of air pollution prevention and control by joint efforts of local governments in the Beijing-Tianjin-Hebei region from 2006 to 2021 was established. Logistic regression, structural equation models, qualitative comparative analysis, and case studies were employed. The results of this paper suggest that the formation of collaborative governance is mainly attributed to internal motivations, and hierarchical interventions indirectly affect collaborative governance through internal motivations. Defining the participation scope reduces the probability of collaborative governance formation by weakening internal negotiations, while formulating collaboration and accountability mechanisms increases the probability of collaborative governance formation by enhancing internal legitimacy. The use of specific combinations of hierarchical interventions by higher levels of government to local governments with power asymmetries can promote the formation of collaborative governance.On the one hand, this study enriches the theories of collaborative governance and hierarchical interventions, constructs a complex logical relationship between hierarchical interventions and horizontal elements, and systematically restores the formation process of collaborative governance. On the other hand, the findings of this study provide policy recommendations for higher-level governments to select hierarchical interventions and achieve collaborative activities or collaborative governance goals in the Chinese policy context.