Composer and singer. After instruction with Giovanni Animuccia in Rome, he studied with Scipione delle Palle in Florence, under Medici patronage. By 1579 he was singing at the Medici court. His earliest known compositional endeavor came in 1589, when he contributed a song to an intermediofor the marriage of Duke Ferdinand I. Initially his fame spread chiefly through his singing: by the 1580s he was singing regularly for Ippolito Aldobrandini in Ferrara and for the Este court there. During the 1570s and 1580s he began a celebrated association with the "camerata" of Florence, and partly under the influence of its members--including Vincenzo Galilei and Bardi--he began composing in a vocal style that, as he declared, more closely approximated speech. After a brief appointment in Rome as Bardi's secretary (1592), Caccini returned to Florence; during the 1590s he served the Medici court, where he became music director in 1600. That year he discussed his new vocal style in the preface to his opera Euridice.
In 1602 (1601 old style) Caccini published the epoch-making Le nuove musiche,a collection of solo songs with basso continuo;its preface discusses the monodic style in detail, describing the proper way to ornament a song and warning against abuse. The pieces themselves manifest the relatively new practice of writing out implicit embellishments. Beginning about 1610 Caccini frequently took part in chamber concerts for Grand Duke Ferdinando de' Medici; 1610 was also the year in which he was made director of sacred music at S. Nicola.