NEW YORK — If you skip “The Perfect Couple,” which starts previews at Off Broadway’s DR2 Theater June 9, you not only will miss the latest play from Brooke Berman (“Hunting and Gathering”) but also the entire 2008 season from Women’s Expressive Theater.Founded in 1999 to support female artists, WET produces just one play a year, and it’s not the only New York company opting for that unorthodox model. But orgs that choose to go the one-a-season route invariably grapple with funders and audiences expecting more. In the world of charitable giving, for instance, guidelines often oppose a single-show slate. The American Theater Wing recently rejected a funding application from WET, stating in a letter sent to the company that it “is not producing a sufficient number of productions, with a sufficient aggregate number of performances, to meet our criteria.” That’s a regular refrain for single-show nonprofits. “You’re not doing anything that deserves a slap on the wrist, but it feels like that’s what you’re getting,” says Sasha Eden, WET’s co-exec producer. (The company’s annual budget of $300,000 is supported by some grant money, as well as individual contributions and in-kind donations.) And the longer a company lasts, the more expectations increase. Consider Edge Theater, which has mounted one-play seasons since 2002, including several world premieres by Adam Rapp. “There are always forces pressuring us to do more, coming from our funders and our board of directors,” says Edge a.d. Carolyn Cantor. “There’s a lot of discussion about how, eventually, you can’t keep growing at this level. The assumption is that you want to own a space and produce these massive seasons, but that’s not always the case.” For one thing, a one-show commitment provides the luxury of time. At Edge, designer David Korins, who founded the company with his wife, Canto,might build dozens of set models for a production, which he can rarely do when he works with other companies. And Cantor, who regularly helms regional and Off Broadway projects, might rehearse with an Edge ensemble for months, instead of the scant weeks given to most shows. The company also stays small — its annual budget is roughly $200,000 — so that it can find an ideal space for each production. Its 2005 staging of Craig Wright’s “Orange Flower Water” was moved to an in-the-round theater at the last minute, because Cantor felt it would help the show. In 2004, the company even experimented with mounting two shows simultaneously, pairing a high-profile run of Rapp’s “Stone Cold Dead Serious” with “Now That’s What I Call a Storm,” by lesser-known scribe Ann Marie Healy. It was a short-lived endeavor. “We had this idea that doing two plays at once would feel really exciting, but ultimately it stretched us too thin,” Cantor says. (Citing personal reasons, she adds that Edge won’t produce in 2008, though it will likely return in 2009.) For some theaters, a one-show season is crucial to maintaining other programs. Before Page 73 Prods. preemed Jason Grote’s “1001″ in 2007, or Quiara Alegria Hudes’ “Elliot (A Soldier’s Fugue)” in 2006, it gave both writers a yearlong fellowship. The company, which has an annual budget of about $225,000, also hosts a writer’s group, a residency program at Yale U. and regular workshops for its stable of scribes. “We want to provide comprehensive support, and to us, that doesn’t just mean productions,” says Page 73 co-exec director Asher Richelli. “It means providing other resources that writers need.” This fall, Page 73 will mount Dan LeFranc’s play “Sixty Miles to Silver Lake” as a co-production with Soho Rep, but that theater has a bigger profile and a broader audience base. “We’ve been very careful in terms of marketing materials,” Richelli says. “Soho has been respectful of the fact that we don’t want to get lost in the mix. We want it to be clear this is our production this year.” To extend its brand beyond a single annual production, WET also mounts readings and workshops of films and screenplays (including an early run-through of Adrienne Shelley’s “Waitress” that helped galvanize that indie production), also running an education program that teaches high school girls how to evaluate cultural portrayals of women. “When our one show and our outreach program are fully funded and staffed, then we’ll think about adding another production,” Eden says.