He was the older brother of another important, and somewhat more progressive composer of the same period, Giovanni Francesco Anerio.
Around this time, he began to compose, especially madrigals; this was one of the few periods in his life during which he wrote secular music.
These positions must have given him considerable opportunity to exercise his compositional talents, for he had already written the music, songs, madrigals, and choruses for an Italian Passion Play by this time.
Anerio was a conservative composer, who largely used the style of Palestrina as a starting point, at least after his youthful period of writing secular works, such as madrigals and canzonettas, was done.
In his very last works, the influence of Viadana, the popularizer of the basso continuo, is evident, but he still remained true to the Palestrina style in his melodic and harmonic writing.