Chief of Department Terence Monahan announced his retirement on Thursday.

Monahan joined the force in 1982. Throughout his career, he worked in precincts and units in Manhattan, Queens and the Bronx.

He became the 40th chief of department in 2018, overseeing 40,000 uniformed officers and civilians.

Monahan announced that he will be replaced by Chief of Detectives Rodney Harrison. Harrison made headlines in 2019 when he became the city's first Black chief of detectives.

Harrison joined the force in 1992 and has served in stations housed in Queens, the Bronx and Brooklyn.

The NYPD chief of department is the highest-ranking uniformed post.

Mayor Bill de Blasio named Monahan as senior advisor of recovery safety planning.