Over the past two decades of conflict, women have served with valor and continue to serve on combat aircraft, naval vessels, and in support of ground combat operations. The expansion of roles for women in the Armed Forces has evolved since the early days of the military when women were restricted by law and policy from serving in certain occupations and units. Women have not been precluded by law from serving in any military unit or occupational specialty since 1993 when Congress repealed the remaining prohibitions on women serving on combatant aircraft and vessels. However, Department of Defense DOD policies have prevented women from being assigned to units below brigade level where the units primary mission was to engage directly in ground combat. This policy barred women from serving in infantry, artillery, armor, combat engineers, and special operations units of battalion size or smaller. On January 24, 2013, then-Secretary of Defense Leon Panetta rescinded the rule that restricted women from serving in combat units and directed the military departments and services to review their occupational standards and assignment policies and to make recommendations for opening all combat roles to women no later than January 1, 2016.