Advances in multimedia digital signal processing (DSP), wireless communication systems, integrated circuit technology and portability requirements have fuelled research into the design of energy-efficient deep submicron (DSM) systems. Noise has emerged as a problem of significance for design in the DSM regime. This research addresses the dual challenge of designing reliable and energy-efficient DSP systems in the presence of DSM noise. Three coupled approaches are being explored: 1) algorithmic noise-tolerance (ANT) that employs stochastic signal processing techniques to combat DSM noise, 2) noise-tolerant dynamic circuit design techniques that provide noise-immunity with minimal energy penalty and 3) a CAD methodology that optimally folds the results of 1) and 2) in order to achieve a specified degree of system reliability and energy-efficiency.