Hyaluronic acid (HA) is found in extracellular tissue in many parts of the body. It is a material of increasing importance to biomaterials science and is finding applications in diverse areas ranging from tissue culture scaffolds to cosmetic materials. Its properties, both physical and biochemical, in solution or hydrogel form, are extremely attractive for various technologies concerned with body repair. This book considers the materials science behind some of the important biomedical and therapeutic applications that are emerging for HA. Key characteristics such as its mechanical properties, biological function and degradation are discussed. The latest technologies in chemical modification and crosslinking strategies are analysed and emerging applications in soft and hard tissue repair are highlighted. The first objective of the book, which consists of a collection of chapters from leading researchers across the globe, is to highlight the role of HA based hydrogels as scaffolds in sustaining stem cells for transplantation and regrowth. The second objective is to detail the significant influence of HA derived materials in the latest advances in cancer therapy, general therapeutics and cosmetics. The third objective is to link the structure-property relationships of HA to medical function and application while reflecting on current clinical and market trends. The book will be of interest to those involved in HA research for medical device and therapeutic applications. Graduate and undergraduate students engaged in the fields of biomedical engineering, materials science, chemistry, medical science, pharmaceutical science and polymer science will find this book of particular interest.