1st Mission Support Command

1st Mission Support Command is a United States Army Reserve command providing support to military units based in Puerto Rico and the US Virgin Islands. Headquartered at Fort Buchanan within the metropolitan area of the Puerto Rico's capital San Juan the command consists of 35 units and fields 3,800 soldiers.

Subordinate units
As of 2017 the following units are subordinated to the 1st Mission Support Command:


 * 1st Mission Support Command, at Fort Buchanan, Puerto Rico
 * 166th Regional Support Group, at Fort Buchanan, Puerto Rico
 * 346th Transportation Battalion, at Roosevelt Roads Naval Station, Puerto Rico
 * 393rd Combat Service Support Battalion, at Fort Buchanan, Puerto Rico
 * 210th Regional Support Group, in Aguadilla, Puerto Rico
 * 35th Signal Battalion, at Fort Allen, Puerto Rico
 * 77th Combat Service Support Battalion, in Aguadilla, Puerto Rico
 * 448th Engineer Battalion, at Fort Buchanan, Puerto Rico