An applicant for membership must be at least 18 years of age. She must prove that she is a blood descendant from an ancestor who provided service in the cause of American independence. Acceptable service, in accordance with the NSDAR by-laws, generally includes service during the period from April 19, 1775 (Battle of Lexington) through November 26, 1783 (Withdrawal of British Troops from New York):
Signers of the Declaration of Independence
Military Service (Continental Army, local militia, etc.)
Civil Service (state, county, or town official)
Patriotic Service (members of patriotic assemblies, signers of Oath of Allegiance, etc.)