Cells are the basic units that make up our tissues and perform bodily functions. In some cases, cells may not function properly. Cell therapy involves placing new or altered cells into the body to replace or repair the damaged ones or delay the progression of a disease. A gene is a unit of DNA which instructs the formation of proteins that often perform important functions in the body’s cells. Sometimes, there can be errors or mutations in the genes, leading to genetic diseases which can be passed down to future generations. Gene therapy involves the introduction of a healthy copy of the gene into the cells, to treat or potentially cure genetic diseases. In some cases, a therapy can be considered to be both a cell and gene therapy. The genes in specific types of cells can be modified before being (re)introduced into the patient to fight disease, address a gene mutation, or restore cell function. By harnessing the power of these rapidly developing technologies, we can potentially treat diseases for which there are currently no treatments.