Defence Evaluation and Research Agency

The Defence Evaluation and Research Agency (normally known as DERA) was a part of the UK Ministry of Defence (MoD) until July 2, 2001. At the time it was the United Kingdom's largest science and technology organisation. DERA was split into two organisations: short-lived transition bodies known as PDERA ("privatised" DERA) which became a commercial firm, QinetiQ, and "RDERA" (meaning "retained" in Government DERA) which became the Defence Science and Technology Laboratory (Dstl).

At the split, QinetiQ was formed from the majority (about 3/4 of the staff and most of the facilities) of DERA, with Dstl assuming responsibility for those aspects which were best done in government. A few examples of the work undertaken by Dstl include nuclear, chemical, and biological research. In the time since the split both organisations have undergone significant change programmes. QinetiQ has increased its focus on overseas research with a number of US and other foreign acquisitions, whereas Dstl has a major rationalisation programme aimed at changing many aspects of its operations.