Her primary areas of practice are civil law, corporate law, securities, real estate and business litigation and arbitration. Since joining the DLA Piper firm in December 2002, Mackiewicz has devoted between 100 to 250 hours to pro bono work each year. A sizeable portion of her pro bono work has been done through House of Ruth Maryland, one of the nation's leading domestic violence centers that helps thousands of victims of domestic violence and their children find safety and security. Between 2003 and 2005, Mackiewicz served as pro bono counsel to the City of Baltimore, took control of abandoned, derelict homes in some of the roughest neighborhoods. She has also served as the chairperson of DLA Piper's partnership with B 4 Students, which created a monthly mentoring program for 15 high school students.