Please contact us if you have questions about the Corps, our application and selection process, or how you can make a difference in the health and well-being of others as a Commissioned Corps officer. You may e-mail firstname.lastname@example.org or call the Office of Commissioned Corps Operations at 800–279–1605. Our standard office hours are Monday through Friday, 8:30 a.m. to 4:30 p.m. (Eastern Standard Time). The office is closed on Federal holidays. If you call outside of business hours, please leave a message. We will return your call as soon as possible.