This book challenges many assumptions commonly used in structural topology optimization. These assumptions include: (1) to find the unique and globally optimal solution-the 'best' design, (2) under prescribed support conditions, (3) for given loading conditions, (4) within a predetermined design domain, and (5) without considering the designer's aesthetic preferences. Through a systematic discussion and numerous examples, this book clearly shows that the traditional assumptions are not only unnecessary, but also imposing severe limitations on design freedom and hindering creativity in structural design. The generalized topology optimization framework presented in this book breaks the mold of many conventional thoughts in structural topology optimization. The new framework will enable topology optimization techniques to solve a much wider range of practical problems. This book appeals to researchers and graduate students working in structural design and optimization and is of interest to civil and structural engineers, architects, mechanical engineers, and product designers involved in creating innovative and efficient structures. This is open access book.