The National Society of Genetic Counselors encourages the sharing of genetic variant, phenotype and interpretation data acquired by clinicians and laboratories through clinical genetic and genomic testing. Timely data-sharing in non-proprietary databases is essential to improve accuracy of variant interpretation. These databases should be designed to protect patient confidentiality and should label variants clearly to indicate how much evidence underlies any variant classification. By broadening access to data about human genome variants, data-sharing allows for more consistent, accurate variant classification across laboratories. For this reason, responsible data-sharing is in the best interest of patients who rely on genetic testing to facilitate their access to optimal medical management and treatment plans.