A hereditary cancer syndrome is a genetic predisposition to certain types of cancer, often with onset at an early age, caused by inherited pathogenic variants in one or more genes. Most hereditary cancer syndromes exhibit autosomal dominant inheritance. The most common hereditary cancer syndromes related to women’s cancer include hereditary breast and ovarian cancer syndrome, Lynch syndrome, Li–Fraumeni syndrome, Cowden syndrome, Peutz–Jeghers syndrome, and hereditary diffuse gastric cancer. A hereditary cancer risk assessment is the key to identifying patients and families who may be at increased risk of developing certain types of cancer. Assessments should be performed by obstetrician–gynecologists or other obstetric–gynecologic care providers and should be updated regularly. An assessment includes information on personal and family history, including pathology, imaging reports, and evaluation of other medical risk factors for cancer. If a hereditary cancer risk assessment suggests an increased risk of a hereditary cancer syndrome, referral to a specialist in cancer genetics or a health care provider with expertise in genetics is recommended for expanded gathering of family history information, risk assessment, education, and counseling, which may lead to genetic testing and tailored cancer screening or risk reduction measures, or both. Currently, genetic testing is guided by personal history, family history, pedigree analysis and, in some cases, risk models that may include pathology reports and confirmation of cancer diagnoses with medical records, death certificates, or both. Counseling before and after genetic testing is an important part of the process to discuss rationale for any genetic testing, disclose results, define other cancer risks, identify educational needs, and secure referrals if necessary for ongoing management. This revision includes updates related to hereditary breast and ovarian cancer, cascade testing, and referrals to genetics specialists.