Buildings and other structures should be designed to resist the worst effects of the strongest winds likely to occur within their design lifetimes. After a description of tropical windstorms and storm surges that can occur in coastal regions, this Note deals with some of the reasons why buildings suffer extensive damage. Then the first step in the design process, the assessment of maximum wind speeds, is discussed. Where specific data are not available, the reader is given some useful sources of information on which to base a design. There then follows a section explaining the nature of airflow around buildings, which leads on to an assessment of pressures and forces for design purposes. Data published elsewhere is not extensively reproduced (particularly as there are so many different shapes of structure possible, and each one would generate its own peculiar wind flow pattern and set of pressures), but many references are given.