The leading lights of musical theater will sing “Happy Birthday” to the great Broadway composer-lyricist Stephen Sondheim on his 80th birthday in two New York Philharmonic concerts next week.

The concerts, Monday and Tuesday at Lincoln Center, will include songs and orchestral pieces from Sondheim musical-theater favorites like “Company,” “Follies,” “A Little Night Music,” “Sweeney Todd,” and “Sunday in the Park with George,” in addition to rarely heard material.

Tony Award-winner Sondheim is considered by many to be the greatest Broadway composer and lyricist of his time.

In addition to writing the music and lyrics for plays, he co-composed the music for the film “Reds” in 1981.

Actor David Hyde Pierce will host the celebration.