环保NGO的政策倡导在近些年被广泛地研究。相比于其他国家和地区，在中国的环保NGO进行政策倡导时，多见采取合作型的方式。现有的研究，更多的是针对某一具体环境政策或者议题进行的政策倡导方式加以解构、梳理和分析，而较少有从某一个组织的角度，从政策倡导的战略设计、规划和实施进行具体政策倡导案例的剖析。本文以N基金会的政策倡导项目为案例，研究其在近二十年间的项目实施过程中采用的政策倡导方式，分析其政策倡导方式的演变和所产生的影响。研究发现，环保NGO选择合作型的政策倡导，一方面是为了获得更好的倡导效果，另一方面是基于政府与组织之间的关系做出的策略性选择。虽然政府与组织关系的变化对政策倡导的方式和效果有重要影响，然而，在外部因素不断变化的情况下，环保NGO仍然可以通过挖掘自身可以获取的资源和自身可以改善的空间，让政策倡导卓有成效。

The policy advocacy of environmental NGOs has been extensively studied in recent years. Compare with the environmental NGOs in other countries and regions, the environmental NGOs in China are conducting the policy advocacy in a more cooperative way. Existing researches are more about analyzing the policy advocacy for a specific environmental policy or theme, but less about the strategic design, planning and implementation of policy advocacy from the perspective of an organization. Taking N Foundation as a case study, this article analyzes its policy advocacy as well as the evolution and impact along the project implementation process in the past two decades. The study showed that choosing cooperative policy advocacy is the rational choice for environmental NGOs in China to meet the need of achieving better outcome, while maintaining secure relationship with the government. Although the changes in the relationship with the government may influence the policy advocacy in a significant way, environmental NGOs can always find room for better impact by optimizing the resources they can obtain and the improving the capacity of the organization.