The work presented in this thesis describes the synthesis and stability of a range of hydrido and low oxidation state complexes of the group 13 elements. The underlying theme is the stabilisation of these species. The work upon this subject is divided into eight chapters. Chapter One provides a general introduction to the members of group 13, with particular emphasis on the development of group 13 metal trihydrides and low oxidation group 13 metals. The reasons behind the inherent instability of these species are discussed, and is the development of stabilising ligands.Chapter Two discusses the variability in the stereoelectronic character of stabilising ligands and describes the development of a number of probes to quantify the stereoelect...