Since the last quarter of the 20th century, humanity has been witnessing the final political-economic and social transformation in history. Matters related to the issues such as planning, city, urban management have been identified for reconsideration. Adopting the concept of an entrepreneurial state instead of a welfare state led to a change in the planning paradigm of this transformation process that began in the mid-1970s and affected the entire world. In this framework, instead of the top-down planning approach, in an approach where the idea of participatory planning based on communicative rationality and that cares about the locality and supports the collaborative planning is adopted and put into practice, in thec context of a horizontal hierarchy. In Turkey, experiences within the context of participatory planning approach are varied. One of the most up-to-date of these experiences is the 1/100,000 scaled Mersin Environment Plan, which is an upper-scale plan produced for the entire Mersin, approved by the Mersin Metropolitan Municipality on 10.10.2016. The aim of this study is to contribute to the plans by transferring the participation experience gained in the process of creating the Mersin Environmental Plan. This study, which is limited to the participation section of the Mersin Environment Plan, includes findings on the process of participation. The success of the process is assessed under the headings of performance indicators such as equality, knowledge, method, and responsibility, and it is discussed via a descriptive approach.