Long before every third person you met in the art world identified themselves as an “art adviser,” there was Thea Westreich Wagner.

She and her husband Ethan Wagner have been art collectors and the dual force behind Thea Westreich Art Advisory Services for over 30 years, but effective April 1, the business will be turned over the their longtime business partners, Suzanne Modica and Ashley Carr.

“During these three-plus decades we’ve enjoyed many marvelous experiences collaborating with private art collectors and assisting in building a number of extraordinary collections,” the pair said in a press release. “We’re fully confident that Suzanne and Ashley will lead the firm forward with the diligence, professionalism, and sharp eyes for the best material that we are known for.”

In 2012 Westreich Wagner and Wagner announced their plans to donate over 850 works of art from their personal collection to the Whitney Museum and the Centre Pompidou, which are planning exhibitions in 2015 and 2016, respectively, of the couple’s gifts (see 800 Works Donated to Whitney, Pompidou).

Their collection boasts work by Christopher Wool, Jenny Holzer, Jeff Koons, Eija-Liisa Ahtila, Dan Flavin, Robert Gober, and Richard Prince.

“In the coming years, we will be able to more fully focus on our gift…and [on] a number of long-delayed, exciting artists’ books and projects we have been planning,” the couple said.

Modica and Carr have been with the company for a combined 21 years (Modica for 13 and Carr for eight), and are “thrilled to have the opportunity to continue the groundbreaking practice that Thea created over 30 years ago.”

The firm will be renamed with the acronym TWAAS, but will “carry forward the same intellectual rigor, integrity, curiosity, passion, and attention to service that became synonymous with Art Advisory Services.”