“We are not going to do pre-collections, collections, post-collections,” he said. “It’s going to be about things I believe are relevant to make. We are just beginning now. And we are beginning really, really small. I like the idea of starting small today.”

The company, which is described as a joint venture, — though Mr. Elbaz said Richemont was the majority owner — will be based in Paris.

“I didn’t want to call it Alber Elbaz, because it’s not about me, myself and I,” he said. “It’s going to be about we and us. And it’s going to go from A to Z.” (He means that literally and metaphorically: The name is composed of the first and last letters of his name, and also refers to his approach.) It is also going to be about luxury, but, he said, “today luxury is not just about price.”

Mr. Elbaz, 58, who during his 14-year tenure at Lanvin became synonymous with a certain grace and generosity of aesthetic, and who was widely beloved in the industry both for his skill with a seam and his willingness to embrace and express his own neuroses, has been largely off the fashion map for the last four years.

Though he became active on Instagram after leaving Lanvin (he has about 124,000 followers), did the occasional collaboration — with LeSportsac and, more recently, Tod’s — and though his name was often raised in speculation when top designer jobs became available, he often seemed ambivalent about re-entering the modern fashion industry, one driven by social media, influencers and a constant stream of product. Indeed, he has been one of its most vocal critics.