This Book concerns floor vibration, describes the nature of floor vibration and provides options for avoiding it through design, or in the case of existing buildings, reducing or eliminating it through alterations. Excessive floor vibration has become a great problem as new rhythmic activities, such as aerobics, generators, air conditioners and long-span floor structures have become more common. The current push towards stronger concrete materials and the use of prestressing results in increasing fineness and dynamism of long-span concrete floors in buildings. Although concrete floors have a good vibration serviceability track record, this trend may lead to an increasing number of floors fails from vibration serviceability. There is a current trend towards even more slender concrete floor structures, which results in more frequent problems with their vibration serviceability. Predictive methods for vibration serviceability must consider not only the structures themselves, but also the non-structural elements which are attached to them, as these may have a significant effect on the dynamic characteristics of the floor structural system.