This bulletin discusses the use of solar control glasses in sufficient detail to help with basic design decisions. It describes the environmental conditions that lead to the need to use solar control glass and lists the properties of the available glasses. It emphasizes the need for careful design and handling to prevent thermal fractures and publishes for the first time a technique, devised by the Pilkington Technical Sales Laboratory, that enables the thermal safety of an installation to be predicted. In some sections, notably the environmental and glazing practice sections, only the aspects important to the application of solar control glasses have been selected for discussion and reference is made to documents in which these matters are treated in detail.