This book is structured in four parts: First, it analyzes the sustainability objectives established for the building stock and the importance of thermal comfort in this aspect. Second, the existing adaptive thermal comfort models and the main energy-saving measures associated with these models are analyzed. Third, the energy savings obtained with these measures are analyzed in several case studies, comparing the results obtained with other energy conservation measures, such as the improvement of the façade. The analysis is carried out from an energy and economic perspective. Finally, a decision�making process based on fuzzy logic is established. As an expected result, the content of the book contributes to assist architects in designing more efficient buildings from the perspective of user behavior.