Buenos Aires is 2 hours ahead of Atlanta during US winter (EST), and 1 hour ahead during US summer (EDT). When it's 9:00 AM in Atlanta, it's 10:00 AM or 11:00 AM in Buenos Aires.
Argentina uses ART (UTC-3) year-round and doesn't observe DST.
Business hours overlap significantly! 9:00 AM - 5:00 PM Atlanta corresponds to 10:00 AM - 7:00 PM Buenos Aires. The manageable time difference makes coordination convenient.
Delta and American operate flights between Atlanta and Buenos Aires Ezeiza International Airport.