The need for the expansion of power grids will increase enormously worldwide in the coming years and decades. This growing need is globally driven by the decarbonization of power generation and the simultaneous substitution of fossil energy sources by electricity applications, among other things in the areas of industry, mobility, building heating, and hydrogen production. It affects transmission and distribution grids equally. Cross-border electricity exchange plays a special role in this context (Chap. 7 ). This chapter examines the forecasts of the expansion needs for power grids in the major economic nations and describes the approval practice in the European Union and presents it exemplary in some countries. The approval procedures in Germany are described in greater detail due to their complexity and extensive nature. Many of these procedural elements can also be found in the approval procedures of other countries, sometimes in a modified form. In most countries of the world, environmental impact assessments play a central role in line projects, especially at the high and highest voltage levels, alongside considerations of energy-related and economic necessity. Their purpose is to ensure that interventions in nature and landscape are kept as low as possible during the necessary grid expansions.