The preparation of silicon germanium microstructures, their physical, chemical and electrical characterization, and their device processing and application are reviewed in this book. Special emphasis is given to ultrathin Si/Ge superlattices. Topics covered include: Wafer preparation and epitaxial growth; surface effects driven phenomena, such as clustering, segregation, 'surfactants'; Analysis, both in situ and ex situ; Strain adjustment methods; High quality buffers; Modification of material properties by quantum wells and superlattices; Devices: Novel concepts, processing, modelling, demonstrators. The questions highlighted, particularly those articles comparing related or competing activities, will provide a wealth of knowledge for all those interested in the future avenues of theory and applications in this field.