The region did ''very well,'' Civil Defence Otago emergency management controller Chris Hawker said.
''We're better this afternoon than we were this morning.''
However, Mr Hawker said there were some challenges authorities ''had not considered''.
For example, losing oil refinery capacity in the North Island might not seem like a local or regional problem, but it raised the national issue of ''who could help'', Mr Hawker said.
''These are areas that need work.''
Nationwide organisations and staff took part in yesterday's national test, and Mr Hawker said Otago was ''very good'' alongside the rest of the country.
''And the more tests we undertake, the better we'll get,'' he added.
''The public can be confident in New Zealand's Civil Defence. We're going to significant lengths to improve connections and make communication better.''
Emergency management Otago recognises tsunamis as one of the major threats to coastal areas in the region.
The Waitaki District, Dunedin City, and Clutha District Councils activated their responses during the first of three simulation exercises.
Landlocked Queenstown Lakes District and Central Otago District Councils contributed personnel during the test.
Two more exercises are planned later this month.
Civil Defence Minister Nikki Kaye said the second exercise would focus on the response after the tsunami had hit, while the third test would look at the long-term recovery after the tsunami.
-By Mandy Te
