Dominguez joined Exelon in 2002 as Associate General Counsel, responsible for all litigation matters in the Mid-Atlantic region. In 2004, he was named General Counsel for PECO. In 2007, he was named Senior Vice President of State Regulatory and Government Affairs and General Counsel of Exelon Generation Company. His role expanded in 2009 to include Senior Vice President of Communications and in 2010, he was named Senior Vice President of Federal Regulatory Affairs & Public Policy for Exelon Corporation. In 2012, Dominguez became Senior Vice President, Governmental and Regulatory Affairs and Public Policy for Exelon Corporation, and in 2015, he assumed his current role.