This thesis is commissioned by Adventure Partners which offers outdoor courses and activities. The aim of this commission is to create a viable sustainability plan for the company which they can take into use. The company’s need for the sustainability plan is to use it as a part of the Sustainable Travel Finland program and to obtain the certificate from the program. The success criteria for this project are to create a usable sustainability plan, to stay on schedule, and to reach the satisfaction of the commissioner. This is a product-based thesis, and the outcome of the thesis is a sustainability plan for the commissioner. The sustainability plan introduces the commitment of the commissioner to sustainable development, it discusses the commissioner’s current sustainable development state and includes the sustainability objectives for the company’s sustainable development. It also discusses responsible management and responsible communication. The sustainability plan is based on the theoretical framework of this thesis and the Sustainable Travel Finland guidelines. The theoretical framework of this thesis discusses both Corporate Social Responsibility as a whole entity and responsible management. The Corporate Social Responsibility part consists of all the three areas of sustainability and introduces responsible communication and motivations for responsible business as well. The responsible management part discusses the tools for responsible business and the standards and benefits of the Sustainable Travel Finland program launched by Business Finland. The theoretical framework of this thesis also introduces the commissioner, its current state of sustainable development, and its future prospects. The actual sustainability plan consists of several different parts. The commitment part explains what is the commissioner’s sustainable development commitment and how the employees are trained towards sustainability. The code of conduct part is a set of guidelines that indicates what is expected from the employees. The sustainability objectives are divided into the three sustainability areas, which all introduce the objectives for sustainable development and the actions for reaching the objectives. The responsible communication part explains how the commissioning company will communicate its sustainable development to different stakeholders. The responsible management part introduces how constant sustainable development is monitored. The sustainability plan is used in the commissioning company to reach out to the Sustainable Travel Finland certificate and to increase transparency for the stakeholders both internally and externally. Ultimately, the success of this project is assessed by using the process success criteria introduced in the introduction part. The project stayed on the new schedule made when the actual project was started, the project aim and sub-goals were reached, the commissioner was satisfied with the final outcome, and the viable sustainability plan was created, thus, the project criteria were succeeded.