Arizona State University is giving the students of a struggling business school a real gift this year: A second chance.

Arizona State University has completed its deal to take over the Thunderbird School of Global Management, the last chapter in what has been a yearslong saga for the troubled Glendale, Ariz., business school.

Under the deal, Arizona State will pay off about $22 million in debts owed by Thunderbird, and beef up the school’s executive education and online programs to boost revenue. Thunderbird’s land is worth more than $22 million, according to Arizona State President Michael Crow. Thunderbird is also contributing $20 million to cover continuing operating losses as the institution stabilizes.

Thunderbird will keep its name and campus but become a quasi-independent part of the Arizona State enterprise, with the majority of faculty and staff staying on. It will stop offering M.B.A. degrees after this school year, and will instead focus on its master’s program in global management, the specialized degree that earned the school renown in the decades after World War II.

Mr. Crow said the deal allows Arizona State to “enable, empower, secure, protect and enhance” Thunderbird. “This is a competitive world. Thunderbird’s back in the game.”

Thunderbird trustees began seeking potential partners in late 2012, as enrollment at the stand-alone business school slumped and cash grew tight. They agreed in spring 2013 to a deal worth up to $52 million to sell the campus to and partner with Laureate Education Inc., a private college operator. After multiple trustees resigned, an alumni group revolted and an accreditor rejected the proposal, the two parties abandoned the effort in April of this year.

Arizona State and Thunderbird entered serious talks over the summer and spent the past few months hashing out details of Thunderbird’s finances and how it would function alongside Arizona State’s well-established W.P. Carey School of Business. To steer clear of Carey’s turf, Thunderbird will offer the one-year graduate global management program, a two-year graduate degree in global affairs and management, certificate programs and executive education.

The deal has already been approved by the Arizona Board of Regents and the schools’ accreditor, the Higher Learning Commission, and is expected to close by Dec. 31, once final details are ironed out with the U.S. Department of Education and Thunderbird’s creditors.