A native of Naples, Ferrara began his career with the youth system of hometown club Napoli in 1980. He graduated the "primavera" youth squad in 1984, and began to earn first team call-ups that season. He made 14 total appearances with the club in his first full season. The following season, Ferrara became a part of the starting XI, and he soon began earning call-ups to the Italy national team, making the squad for the 1990 FIFA World Cup. He also scored one of Napoli's goals as they won the 1989 UEFA Cup final. In addition to the UEFA Cup, with Napoli he won two Serie A titles (in 1986–87 and 1989–90), the 1987 Coppa Italia final, and the 1990 Supercoppa Italiana, the latter over his future team, Juventus.