Technological innovations that cover virtually every branch of medicine and health care are necessary to provide safe, precise, and thus more efficient prevention and treatment of diseases. This progress is manifested as well in recent advancements in functional nanomaterials and nanotechnologies for diagnostics, therapeutics, and drug delivery systems, showing increasingly promising outcomes in clinical trials. In this Special Issue, we would like to highlight the growing interest in this field of advanced functional nanomaterials, currently becoming more and more established. Therefore, submissions covering all aspects of novel nanomaterials and nanotechnologies and their applications throughout the medicinal and healthcare field are welcome.