Two companion articles in this issue report the results of studies of emotional and behavioral effects of terrorist activities in the Washington, D.C., area: the September 11, 2001, attack on the Pentagon and the October 2002 sniper attacks. Thomas A. Grieger, M.D., and his coauthors examined posttraumatic stress disorder (PTSD), alcohol use, and perceptions of safety among 77 survivors of the Pentagon attack after seven months (see page 1380) and, in a separate study, assessed similar variables to determine the emotional and behavioral effects of the sniper attacks among 382 staff at a large tertiary care military hospital (see page 1383). Among their findings was an association between the study variables and gender: female survivors of the Pentagon attack were more than five times as likely as male survivors to have PTSD and almost seven times as likely to report increased alcohol use. In addition, gender, PTSD, and increased alcohol use were all associated with perceived safety. The sniper attacks were associated with substantial changes in perceived safety and assessment of threat as well as decreased activity outside the home. Studies related to the events of September 11 are covered in two additional reports in this issue: a brief report by Sasha Rudenstine and colleagues, who assessed awareness and perceptions of Project Liberty in New York City (see page 1404), and a Frontline Report by Mara Kushner, C.S.W., and Ellen Weissman, M.D., M.P.H., who looked at how a Veterans Affairs health care system in New York and New Jersey has increased support for frontline medical response staff in the past two years (see page 1410).