In January 1497, when the powerful Carafa family translated the relics of San Gennaro, patron saint of Naples, to the city's cathedral, a devastating plague that had ravished the region is said to have immediately ceased. The presence and miraculous power of the saint's relics give meaning to the Succorpo, Cardinal Oliviero Carafa's funerary chapel in the cathedral. This magnificent foundation serves two functions: first, it is the private funerary chapel of Carafa and select members of his family; second, it is the locus of the cult of San Gennaro himself. My thesis examines the chapel's dual functions and explores the iconography of its decoration. I present new propositions regarding the architectural plan and artistic attributions of the chapel, and I provide a close reading of the portrait sculpture of Cardinal Carafa in the Succorpo, considering how its strategic placement informs our understanding of the program and its meaning.