With every decade, the average height of tall buildings has increased and with the near completion of Burj Dubai, tall buildings are now reaching unprecedented heights where the governing limit state has transitioned to occupant comfort. This thesis focuses on the factors influencing the habitability limit state of tall building design through an investigation of data from the Chicago Full-Scale Monitoring Program. After developing and validating a framework for estimating the amplitude-dependent dynamic properties of tall buildings, frequency and damping are extracted from ambient vibration data using both spectral and time-domain approaches. By doing so, not only is much needed information on in-situ damping values made available to aid in habitability design of tall buildings, but structural attributes facilitating amplitude dependence are hypothesized, and the shortcomings of a traditional spectral approach are emphasized. Finally a framework is developed to investigate occupant comfort directly from full-scale accelerations using existing motion simulator studies to project the likely number of occupants adversely affected by tall building motion when considering the effects of waveform, duration, and frequency of oscillation. This framework provides perhaps the most faithful mechanism, outside of tenant interviewing, to evaluate the performance of tall buildings from an occupant comfort perspective.