Glenn Costello will be starting today in the ABS research group at Merrill Lynch as the director responsible for all real-estate ABS, reporting to Dan Castro. Costello worked at Fitch IBCA since 1990, and managed the residential mortgage ratings group there for the past three years. Before that, he worked at Goldman Sachs & Co. for four years. Costello joins Merrill three months after the departure of Chris Flanagan, the former head of real-estate-related ABS research, who left with analysts Ralph Diserio and Ryan Asato to join Chase Manhattan Corp. Regarding Costello, Castro said: "We're real excited to have him, because we need the help!"