Scorsese initially titled the film Wise Guy and postponed making it; he and Pileggi later changed the title to Goodfellas. To prepare for their roles in the film, De Niro, Pesci and Liotta often spoke with Pileggi, who shared research material left over from writing the book. According to Pesci, improvisation and ad-libbing came out of rehearsals wherein Scorsese gave the actors freedom to do whatever they wanted. The director made transcripts of these sessions, took the lines he liked most and put them into a revised script, which the cast worked from during principal photography.
Scorsese initially titled the film Wise Guy and postponed maki.ng it; he and Pileggi later changed the title to Goodfellas. To prepare for their roles in the film, De Niro, Pesci and Liotta often spoke with Pileggi, who shared research material left over from writing the book According to Pesci improvisation and ad-libbing came out of rehearsals wherein Scorsese gave the actors freedom to do whatever they wanted. The director made transcripts of these sessions, took the lines he liked most and put them into a revised script, which the cast w.orked, from during principal photography