DRA has two meanings:
Director, Royal Artillery
A post carrying the rank of Brigadier. The DRA is the professional head of the Royal Artillery in all its guises and forms. He is responsible for policy of all kinds (none of which ever reaches the people who need it), standards (lol!) and lots of other stuff that seems to consume enormous amounts of staff effort for very little return. The titular head of the Royal Artillery is HM Queen as Captain General - accompanied by her Ack, the Master Gunner, St.James Park.
Directorate Royal Artillery
This is the DRA's personal HQ - a veritable orgy of crap. HQ DRA is noteworthy only in that every single officer it employs knows next to nothing about anything except hunting - huge amounts of staff effort were devoted to saving the RA Hunt, and they even created a post for an SO2 to discharge it. Pathetic.
This creates problems when the entire Royal Regiment are conducting close combat operations in Afghanistan and need something more than vague platitudes and utterances of reassurance.
HQ DRA is located in Larkhill. It also has responsibility for a number of subsidiary organisations: