Joshua Bright for The New York Times

The lamentations over the slow death of commercial Off Broadway theater have subsided, at least for a while. It’s true that over the past decade the city has lost at least a half-dozen spaces once devoted to presenting new work unsuitable for Broadway, including the Variety Arts in the East Village, the Promenade Theater on the Upper West Side (now a Sephora) and the Century Center off Union Square. I suppose we can consider it a happy coincidence that none has become a Duane Reade. The result has sometimes been a stampede to Broadway by shows that by all rights should remain Off Broadway. Witness the recent quick flop of the musical “Lysistrata Jones.”

At the same time the established not-for-profit institutions that have long been the mainstay of the Off Broadway movement have not only survived but thrived in a tough economic environment. Between full-scale renovations and major building projects, most of the city’s major Off Broadway companies have been in the process of regeneration – and major fundraising – over the past half-dozen years or more, resulting in some major changes in the landscape.

Manhattan Theater Club, one of the standard-bearers of Off Broadway since its founding in 1970, acquired its own Broadway venue, formerly the Biltmore and now the Samuel J. Friedman Theater. The Second Stage Theater is now housed in a former bank sleekly redesigned by Rem Koolhaas, and it has signed an agreement to establish its own foothold on Broadway, the Helen Hayes Theater. Fund-raising is under way.

Theater for a New Audience, a vital resource for small-scale but often excellent classical theater, broke ground on its $47.5 million theater complex near the Brooklyn Academy of Music in June. Designed by another noted architect, Hugh Hardy, the new complex will feature a 299-seat main stage. This spring one of the city’s most plush not-for-profit theaters, Lincoln Center Theater, will open a second Off Broadway space in a new structure plopped right on top of the Vivian Beaumont Theater. And the venerable Public Theater is in the process of getting a full-scale makeover of its multiple theater spaces.

Perhaps most spectacular of all is the opening this spring of the $66 million Pershing Square Signature Center, the inviting new home of the Signature Theater Company, designed by yet another A-list architectural name, Frank Gehry. As those who have had a chance to visit by now know, the Signature Center is a major upgrade from the Signature’s functional but modest previous home down the street. It boasts three spaces, with seating capacities ranging from just under 200 to just under 300.

You can enter the second floor lobby and café area via elevators or an impressive twisting wooden staircase. Once there you can have coffee or a cocktail after collecting your tickets. The light-filled, open space reminds me of the National Theater in London in the way it opens up theatergoing as a fluid social experience. With three shows going up nightly at the moment, there is an inviting sense of hubbub just before curtain time. At the performance of “The Lady From Dubuque” I saw on Saturday night I happened to run into friends who were coming to see “Blood Knot”; when I went to see “Blood Knot” a few weeks ago I had a chance to say hello to Edward Albee. (A small complaint: With so much thought having gone into the creation of the space – these days all renovations of performance spaces expand the bathroom facilities – it was a bit dismaying that my knees were grinding into the back of the seat in front of me.)

All this impressive building does bring with it potential pitfalls, however. Since it has moved to Broadway, Manhattan Theater Club has sometimes been less judicious in its selection of plays for its Off Broadway space at City Center. The first two plays it presented there this season – Zoe Kazan’s “We Live Here” and Molly Smith Metzler’s “Close Up Space” – were outright duds. Although the Public Theater has revived its dedication to Shakespeare in recent seasons, this year the company’s new play slate is on the thin side, with the season dominated by double engagements of the solo show “The Agony and the Ecstasy of Steve Jobs” and the return of “Gatz.”

Michelle V. Agins/The New York Times

The danger is that these companies, with elaborate new theaters to fill, will lose sight of their missions; the New York theater economy is already unhealthily Broadway-centric, and the idea that bigger is necessarily better is a dangerous one. The development and creation of innovative new work, no matter how great its potential for popular appeal, is the bedrock of the Off Broadway mission, and with new theaters requiring more overhead to keep up, the impulse to go for the safe choice, the name playwright, may be even greater.

I also worry that this mania for building new lavish Off Broadway spaces will spread indiscriminately. There is something to be said for sitting still and maintaining a historic home, after all. I would be dismayed to hear that New York Theater Workshop, for instance, was embarking on a fund-raising drive to build a new theater. The company’s current home on East 4th Street has its logistical inconveniences – there’s no lobby to speak of, and the bathroom are puny – but it remains one of the most appealing theaters in the city, in part because it has the kind of scruffy, repurposed-but-ungentrified feeling that new theater spaces inevitably lack. There’s nothing antiseptic about New York Theater Workshop’s auditorium, and what it lacks in all mod cons it more than makes up for in funky, authentic East Village charm.

And an element in the appeal of the grander Broadway theaters, after all, is the history of prior performances that you feel has seeped into the spaces themselves. There’s no reason the same shouldn’t hold true for Off Broadway theaters. New York Theater Workshop has long been one of the city’s more adventurous not-for-profit houses, and its raw-looking but at the same time majestic auditorium has hosted some of the best new work the city has seen during its tenure, from the musical “Rent” to new plays by Caryl Churchill and the experimental revivals of the Flemish director Ivo Van Hove. It’s been a slightly funky place where you expect to see adventurously funky theater, and I hope it stays that way.

Do you have any thoughts on the new Signature center, the old New York Theater Workshop, or the general state of the city’s Off Broadway institutions? Please share them below.