Lecture provides an overview of the progress made in molecular medicine applying genetics and genomics to the understanding, diagnosis, and treatment of human diseases. Specifically, the methods for identifying genes involved in human diseases are described. Examples from 10 genes and diseases will be provided, drawing on the author’s research. Topics include examples from simple Mendelian diseases, such as cystic fibrosis, inherited cancers, oncogenes activated by chromosomal translocations, host genes involved in infectious disease, genes identified via genomewide association studies, pathogens causing cancer, and gene families contributing to multiple diseases. For each example, historical details will be provided as background for readers to understand the context and process of the discoveries, technologies explained, and current understanding and treatment implications detailed.