At every step that tall building design takes toward the sky, today’s architects and engineers encounter new difficulties. As the height of modern skyscrapers rises with developments in the field of structural system design and the use of high-strength materials, their weight and rigidity decrease, and their slenderness and flexibility – and thus their sensitivity to wind loads – increase. Wind loads, which cause large lateral drift, play a decisive role in the design of tall buildings and can be even more critical than earthquake loads. As a result, the wind loads and lateral drift to which tall buildings are subject have become an important problem (Figure 6.1). Design approaches for controlling wind-induced building sway in tall buildings and protecting serviceability can be divided into three main groups, the “architectural design approach”, the “structural design approach” and the “mechanical design approach” and their respective subgroups.