This Technical Design Report (TDR) for the High-Level-Trigger (HLT), Data Acquisition (DAQ) and Controls of the ATLAS experiment builds on earlier documents published on these systems: Trigger Performance Status Report [1-1], DAQ, EF, LVL2 and DCS Technical Progress Report [1-2], and HLT/DAQ/DCS Technical Proposal [1-3]. Much background and preparatory work relevant to this TDR is referenced in the above documents. In addition, a large amount of detailed technical documentation has been produced in support of this TDR.