The W.N.B.A., which has been without a permanent leader since Lisa Borders resigned as president in October, has appointed Cathy Engelbert as its new commissioner. Ms. Engelbert will take over a league that is working to rebrand itself and engaged in a labor negotiation with a fast-approaching deadline.

Ms. Engelbert was elected chief executive of the accounting organization Deloitte in 2015. At Deloitte, a private company, partners elect the chief executive to serve a four-year term. In March, Deloitte’s partners elected the new chief executive. Ms. Engelbert will join the W.N.B.A. on July 17 after her term ends.

“Cathy is a world-class business leader with a deep connection to women’s basketball, which makes her the ideal person to lead the W.N.B.A. into its next phase of growth,” Adam Silver, the commissioner of the N.B.A., said in a statement Wednesday.

Ms. Engelbert has been with Deloitte since 1986, after she graduated from Lehigh University, where she was captain of the basketball team. She averaged 14 points a game in her senior year as Lehigh won the East Coast Conference tournament. In the title game, Ms. Engelbert scored 20 points and was credited, in The Morning Call of Allentown, Pa., with keeping “the pieces glued together when the cracks started to show.”