The surprising departure of Jed Bernstein last month after just 27 months as president of Lincoln Center was prompted not by a change in career plans, as announced, but by the discovery that he had been in a relationship with a staff member, the organization acknowledged on Tuesday.

The center, the world’s leading performing arts complex, had presented the resignation as a sudden but understandable decision by a cultural leader who wanted to return to producing shows for the stage, where he had spent much of his career.

In reality, Mr. Bernstein, 61, was forced from the top post after an anonymous complaint revealed that he had been involved in a consensual relationship with a woman in her 30s who worked for him — and whom he had twice promoted, according to two people briefed on his resignation. They spoke on condition of anonymity because negotiations over his departure were confidential.

After repeated requests during the past several weeks to elaborate on Mr. Bernstein’s departure, Lincoln Center on Tuesday provided a statement to The New York Times through the crisis management firm Rubenstein. The statement said that in response to the complaint, received in March, Lincoln Center “immediately retained independent outside counsel to conduct an investigation” and “determined that Mr. Bernstein had violated Lincoln Center human resources policy by not disclosing a personal relationship with an employee.”