This paper assesses good practices and lessons learned in investment promotion in European Union (EU) Member States. It focuses on two specific areas of investment promotion: state aid for regional development under EU law and special economic zone frameworks. It provides an overview of the concept of state aid and compatibility of regional aid with the internal market, as well as lessons learned from the case law determining the existence of state aid in regional development measures. It also outlines the calculation of the gross grant equivalent of state aid. The paper explores special economic zone policies, identifies success factors and describes the complementary framework conditions to maximise their spillover effects on local economic development.