Semiconductor quantum dots, also known as "nanocrystals," are structures with electronic and optical properties that can be engineered through the size of the structure, not just the composition. Quantum confinement of charge carriers leads to a wide range of intriguing physical and chemical phenomena, and is a new degree of freedom in material design. Semiconductor quantum dots have potential for applications ranging from optoelectronic devices to biological imaging. The papers selected for this volume treat the fundamental properties of semiconductor quantum dots and form a significant part of the foundation on which the current field of nanoscience research is built.