In all theory, design and specifications, some assumptions are necessary and, as experience is gained, the value and accuracy of these assumptions is made apparent. The ultimate weight and cost of a structure is influenced in no small degree by the initial considerations, and in the particular field under review the question of maximum wind pressures and the law connecting such pressures with height above ground level, are of primary importance. It is the intention of this paper to review briefly the results of past experiments and endeavour to point out what are safe and economic values of wind pressures for design purposes. The need for the standardization of wind-pressure assumptions will also be brought out and it is sincerely hoped that practical action will be taken in the near future.