Located primarily in Washington, DC, and Germantown, MD, the operational offices of the Department of Energy headquarters, houses several program and staff offices, all working to meet the Department's mission to ensure America’s security and prosperity by addressing its energy, environmental and nuclear challenges through transformative science and technology solutions. Of the 15 locally recognized units within the Department, headquarters operations locally negotiates with the National Treasury Employees Union (a single bargaining unit) internally divided into two local chapters representing both professional and non-professional general schedule employees in the Washington, DC, metropolitan area.