The Assistant Secretary of Defense for Research and Engineering (ASD(R&E)) is a senior official of the United States Department of Defense. The ASD(R&E) and the office s/he heads are charged with the development and oversight of DoD technology strategy for the DoD. The ASD(R&E) reports to the Under Secretary of Defense for Acquisition, Technology and Logistics (USD(AT&L)). The post (or effectively the same post) has at various times had the titles Under Secretary of Defense, Research and Engineering (USDR&E), or Director of Defense Research and Engineering (DDR&E). The latter title has itself historically varied between the rank of Under Secretary and that of Assistant Secretary.