The director of Baltimore's Department of Social Services office announced her resignation Tuesday, after seven years leading the agency.

Molly McGrath Tierney said she was leaving to join Bennett Midland, a New York-based management consulting firm, as a senior partner. Her last day will be Feb. 28.

"I am proud of our accomplishments at BCDSS and have decided it is time to take on the new challenge of extending our accomplishments in Maryland to other parts of the country where there is a growing appetite for this kind of success," she said in a statement.

The governor and mayor will jointly appoint a new director of the state agency.

Maryland Department of Human Resources Secretary Ted Dallas called McGrath Tierney "not just a trusted colleague but also a close friend."

"She transformed the Baltimore City Department of Social Services into one of the highest performing agencies in the state and the country and her impact can be felt in every corner of the Department," he said.

Baltimore Mayor Stephanie Rawlings-Blake said she would miss "Molly's wise counsel."

"She was an out of the box thinker, who always fought to deliver the best possible services for those she served. If there was a way to work together and get results, Molly found it," Rawlings-Blake said.

McGrath Tierney was recently involved in a controversial program that allowed some teens in foster care to get a high school diploma in a single day. The program, which involved a Christian school in Philadelphia, ended amid questioning from The Baltimore Sun.

luke.broadwater@baltsun.com