Explanatory Summary of the Content of the Thesis Sustainable entrepreneurship is a subject that has attracted growing research interest. Bringing together the three pillars of sustainability – society, the environment, and the economy – sustainable entrepreneurship is considered by scholars to be a practical and feasible path towards the meaningful integration of people, profit, and planet. In the context of Saudi Arabia, this study analyses the influence of formal and informal institutions on green entrepreneurial activities and their impact on sustainable development. Institutional economics was adopted to frame the hypotheses and analysis. The methodology used was quantitative (regression and panel data models), and the data were obtained from the annual reports of the Authority for Meteorology and Environmental Protection and the General Authority for Statistics (2012–2018). The main findings of this study show that institutions (such as property rights and culture) contribute positively to green (vs. non-green) entrepreneurship, with a positive influence on sustainable development, in Saudi Arabia. The results also demonstrate that green entrepreneurship contributes positively to the economic, social, and environmental components of sustainable development, whereas nongreen entrepreneurship has no effect. This research has both theoretical and practical implications. In terms of the theoretical debate, the study provides empirical evidence highlighting the relevance of formal and informal institutions to green entrepreneurial activities and their influence on sustainable development. Thus, policymakers who are constantly creating strategies can take into consideration that any policy implemented affects green entrepreneurship, generating effective solutions and opportunities in green infrastructure and support for their use by governments, private companies, and all the relevant stakeholders.