Sustainability is increasingly a priority in the policies of the European Union, especially in the Common Agricultural Policy. This paper focuses on Sustainable Development Goals, the European Green Deal, and the Farm to Fork Strategy in an attempt to establish a relationship with the European Union’s trade policy. Three selected components of the agri-food sector—the food supply chain, agri-food quality standards, and global trade—are examined in relation to defined sustainability aspects. The aim is to understand the interrelationship between the three components with specific regard to sustainability, to highlight their high complexity and current relevance, to contribute to systematic analysis in this area, and to present current progress. This qualitative‒explorative study is empirically supported by a survey of market experts, and the Transatlantic Trade and Investment Partnership between the European Union and the United States is used as an example. The results show the complexity between the relationships of the three components with a focus on sustainability and reveal a deep uncertainty. The most notable results are the limited level of knowledge and the insufficient attention from business representatives to sustainability aspects. Finally, the study identifies the state of integrating a sustainable perspective into European Union trade policy and provides suggestions for further research.