A general introduction is made to the basic concepts involved in engineering for systems reliability. Attention is focused on the problems of performing human factors research which will be of maximum usefulness to those making engineering design and management decisions regarding the human element in systems reliability. It is urged that task variables be specified in quantitative units which are compatible with other engineering formulations and that there be greater emphasis on operational analysis under realistic environmental conditions. An idealized methodological approach to human factors research is also described.