This thesis explores the intersection of EU competition law and sustainability, focusing on how Article 101 TFEU supports sustainability agreements within the European Green Deal context. By analyzing the revised 2023 Horizontal Cooperation Guidelines, this study examines how these agreements align with EU competition principles while advancing environmental and social objectives. The study evaluates the practical challenges businesses face when incorporating sustainability initiatives into compliance frameworks and considers the role of national competition authorities in encouraging sustainable practices. Using case studies such as the Car Emissions Scandal, the research underscores the delicate balance between enforcing competition law and promoting the EU’s sustainability agenda. The findings highlight the need for competition law to evolve in support of innovation, fair markets, and long-term societal goals and provide recommendations for future policies that integrate sustainability more effectively.