Liaisons: Stephen Sondheim’s “A Little Night Music” at Signature Theatre in the fall, with Holly Twyford and Bobby Smith. (Christopher Mueller)

Signature Theatre of Arlington, Va., has long specialized in Stephen Sondheim musicals, and now the company is branching out by rescuing the website Everything Sondheim.

The site is an outgrowth of the Sondheim Review, a quarterly magazine of in-depth features and across-the-country reviews of Sondheim stage productions since 1994. That full-court press morphed into Everything Sondheim in 2016, but last year Rick Pender, who ran the Sondheim Review since 2004, announced that the website was not financially viable.

“Promoting on a national basis something that’s niche subject matter proved more than we could accomplish,” Pender said by phone Thursday.

Enter Signature. The troupe has marched side by side with Sondheim for 28 years, staging nearly all the composer’s musicals at least once. The company decided it would bring Everything Sondheim in-house starting this month.

“I’m delighted that Signature is taking over Everything Sondheim,” Sondheim said in a statement. “I’ve had a long and happy relationship with Eric Schaeffer and his theater, and the website couldn’t be in better hands.”

The Sondheim Review and Everything Sondheim have been encyclopedic resources for Sondheim buffs. A national/international listing of shows has been a feature, so you know when “Sweeney Todd” is in Cincinnati or “A Little Night Music,” recently staged by Signature artistic director Schaeffer at Signature, is in Washington. The venture also has been prized for knowledgeable histories and analyses of the musicals.

“It will start out looking familiar,” says Jennifer Buzzell, Signature director of marketing and sales. “But then we hope to round the site out in next year or so with basic Sondheim content — bibliographies, histories, Sondheim 101, and more ‘snackable’ content — quizzes and lighthearted news.” That doesn’t rule out more in-depth writing; Signature will not create all the content, and Pender says he is open to contributing occasionally. (Pender has a large new assignment of his own, writing a Stephen Sondheim Encyclopedia for publisher Rowman & Littlefield.) Signature also aims to add resources for middle school and high school drama programs wanting to put on a show.

Legally, Signature took over the debt-free site Jan. 1 for $10. February is the target for Everything Sondheim to begin showing up on Signature’s site.