The initial chapters focus on principal molecular technologies that underpin the information in the later chapters. In addition to introductory areas of nucleic acids and techniques in molecular biology, bioinformatics and proteomics, other key diagnostic areas such as the use of immunological reagents are covered. The later chapters provide more specialised examples of currently used diagnostic technologies and insights into selected key diagnostic challenges including specific examples of molecular microbial diagnostics and molecular biomarkers in oncology. The running themes through the chapters provides an insight into current and future perspectives in this rapidly evolving field.