This "designers' manual" is made during the TIDO-course AR0531 Smart & Bioclimatic Design. The aim of sustainable design is to create comfortable buildings for the users with the reduction of the use of mechanical systems for cooling and heating, and the maximization of the thermal attributes of the shell and the climate. Natural ventilation can be used as an alternative way of cooling. This manual is for architects and engineers who want to integrate a natural ventilation system in the design of a building.