The goal of USD (R&E) is to extend the capabilities of current war fighting systems, develop breakthrough capabilities, hedge against an uncertain future through a set of scientific and engineering options, and counter strategic surprise.

Under the DoD Reorganization Act of 1958 (PL 85-599, effective 6 August 1958), the position of ASD (R&E) was abolished and replaced by a Director of Defense Research and Engineering (DDR&E).

From 19 May 1961, until 15 July 1965, a Deputy Director of Defense Research and Engineering held the additional title of ASD(R&E), on the theory that this position reported to, in rank, an under secretary—the DDR&E.

On 21 October 1977, PL 95-140 made the rank of the DDR&E unambiguous by renaming it to the Under Secretary of Defense for Research and Engineering (USD (R&E)).

A subordinate position at the assistant secretary level was reestablished with the previous title DDR&E.

However, budget control of the technology portfolio was kept by USD(AT&L), diminishing the importance of the DDR&E position subsequently.