Morelli was trained as a doctor. With his return to Italy he acted as a conduit for intellectual life of the North. His fully-developed technique was published as Die Werke Italienischer Meister, ("The work of the Italian masters"); it appeared under the anagrammatic pseudonym "Ivan Lermolieff".
Morelli's connoisseurship was developed to a high degree by Bernard Berenson, who met Morelli in 1890. The first generation of Morellian scholars also included Gustavo Frizzoni, Jean Paul Richter, Adolfo Venturi and Constance Jocelyn Ffoulkes. Morellian scholarship penetrated the English field from 1893, with the translation of his master work. The Morellian technique of connoisseurship was extended to the study of Attic vase-painters by J.D. Beazley and by Michael Roaf to the study of the Persepolis reliefs, with results that further confirmed its validity. Morellian recognition of "handling" in undocumented fifteenth and sixteenth-century sculpture, in the hands of scholars like John Pope-Hennessy, have resulted in a broad corpus of securely attributed work. At the same time, modern examination of Classical Greek sculpture has turned away from comparable attributions based on style that is reflected in copies.