We report stable and reproducible switching and memory effects in Self-Assembled Monolayers (SAMs). We demonstrate realization of negative differential resistance (NDR) and charge storage in electronic devices that utilize single redox-center- contained SAM as the active component: and compare the effects of various redox centers to switching and storage behavior, The devices exhibit electronically programmable and erasable memory bits with bit retention times greater than 15 min at room temperature. (C) 2002 Elsevier Science B.V. All rights reserved.