Genome editing, including CRISPR/Cas9, is a new and notable technology that enables geneticists and researchers to edit parts of the human genome. The American College of Medical Genetics and Genomics recognizes that genome editing offers great promise for the future treatment of individuals and families with genetic disorders, but also raises major technological and ethical issues that must be resolved before clinical application. The potential for rapid advance of this approach, and the pressure to apply it clinically, should not be underestimated.