This systematic review explores the implications of Brexit on contracts between UK and EU businesses, focusing on the law of contract. It examines the potential impact on trade volumes, investment, supply chains, and regulatory competition. The study also considers the uncertainty, political dynamics, and political contagion that Brexit may cause. The report highlights the consequences of Brexit for English contract law, including legal innovation, citizen rights, and economic relationships. The research aims to provide insights for businesses navigating the post-Brexit landscape.