This thesis explores the integration of the Baltic States (Estonia, Latvia, and Lithuania) into the European Internal Market, focusing on the economic impacts, foreign direct investment, competitiveness, and the challenges and opportunities they face. The research examines the regulatory frameworks governing the European market and the key determinants of business success within this context. The primary hypothesis predicted that the integration of these states into the Internal Market would enhance their business environments, improve competitiveness, and provide new economic opportunities.The analysis reveals that the integration has indeed fostered positive economic growth, increased trade, and improved FDI, particularly through regulatory alignment with EU standards. However, the thesis also identifies ongoing challenges, such as labor shortages, regulatory compliance complexities, and market accessibility issues, which continue to affect business operations in the Baltic region. These challenges, while significant, have not shaded the overall benefits of EU membership. The research concludes that the Baltic States have successfully navigated their integration into the European Internal Market, leveraging it to modernize their economies and boost competitiveness. Future strategies should focus on addressing labor mobility, strengthening regulatory compliance, and harnessing opportunities in digital and green economies to sustain long-term growth.