The increasing world population, along with water and land shortages and climate change, lead growers worldwide to protected cultivation systems. The screenhouse, built with a skeleton of basic construction elements enveloped by a porous screen, is one example of such systems. Another protected cultivation system is a screen cover without sidewalls, usually used for shading only. This chapter describes common types of structures and materials used by growers and discusses studies where microclimate and evapotranspiration were measured and modelled under the screens. The chapter considers the question of whether it is possible to increase water-use efficiency in screenhouses. The chapter reviews studies in which product quality under screens was examined. Finally, the chapter draws attention to knowledge gaps and suggests future research directions.