Building openings provide light, ventilation and climate control for rooms. At the same time, they are essential functional and design elements of facades, enabling communication between indoor and outdoor spaces as transparent or translucent structural components. Similar to the entire building envelope, windows and exterior doors must meet exacting standards for materials, construction types and installation conditions, as well as for fire, noise and thermal insulation, energy efficiency, airtightness and building security. The Building Openings Construction Manual opens with historic developments, provides solid facts on standards and safety features. It covers materials, components, construction types and specifics of structural connections, including solutions on how to deal with existing older windows and issues of ventilation, the use of solar energy and ecological sustainability. Detailed case studies offer a wealth of constructive ideas for the reader's own work.