Response time (RT) is one of the most important variables in Psychology. RT reflects the duration and organization of mental processes, it tells us if a device is easy to handle, or if a patient with brain injury is able to drive a car. In the project we identify current issues in RT measurement, especially the widespread use of conditional RT measures (“mean correct RT”) and poor experimental designs. We investigate different cognitive architectures their associated estimators for unconditional RT performance, and we develop experimental paradigms that more effectively induce time pressure. For the first time after 150 years of RT research, we will lay the foundations for RT measurement in many areas of psychology, including perception, attention, memory, reasoning, decision making, and neuropsychological assessment. In addition, the results will substantially broaden the scope of RT measurement and experimentation.