They are most famously recognized for educating select female pupils (called figlie del coro) to professional levels of musicianship and attracting many European tourists to hear their all-female ensembles perform religious services and special concerts throughout the seventeenth and eighteenth centuries.
Venice had a long history of caring for its sick, homeless, poor, and orphaned before the four Ospedali became recognized as a group musical institutions.
Each catered to a different need: the Incurabili took in all who contracted incurable diseases such as syphilis or the bubonic plague; the Derelitti provided a place of refuge for the homeless; the Mendicanti cared for beggars and orphans; while the Pietà (1346), which was founded from an orphanage, exclusively took in foundlings.
Additionally, the figlie del coro were always required to perform in raised galleries, which had grating that hid the musicians from the eyes of the audience.
By mid-seventeenth century, however, the Ospedali governors realized the economic potential of the cori, and they began to hire many professional external musicians and composers to teach performance practice, sight singing, ear training, music theory, and instrumental techniques.