Representatives of the 19-member NATO nations stand for a group photograph. Representatives of the 19-member NATO nations stand for a group photograph during the commemorative ceremony of the 50th anniversary of NATO held at the Andrew W. Mellon Auditorium, Washington, D.C., on April 23, 1999. SHARE: Download: Full Size (0.06 MB) Credit: VIRIN: 997939-T-QKF79-176.jpg Photo Gallery