The live events sector says the increased capacity at shows is "a long time coming".
From today, indoor gatherings can go ahead with 60 percent capacity while outdoor events can have 75 percent.
Adults must be vaccinated or recently recovered from the virus to reach those capacities.
Religious ceremonies, such as communions and confirmations can resume, while live music is permitted.
Director of the Performance Corporation Jo Mangan says it was tough to watch other industries reopen while the arts remained largely shut.
"We're a really safe industry anyway,, health and safety is woven into everything we do in case sets fall on people or lights fall on people - we're hardcore regulated.
"It has been really difficult to look at things opening up like indoor hospitality, where masks are not part of that protocol."
