 Between 1991-1994, Smith discovered the molecular mechanism by which proteins recognize messenger RNA and participate in site-specific assembly of enzyme complexes to orchestrate the modification of select cytidines to uridines in a process known as C to U RNA Editing.This work has served as the foundation for numerous findings concerning RNA sequence modifying mechanisms and DNA mutating mechanisms that determine cell and protein diversification and was cited for its groundbreaking ideas in an article written by L. Chan for "Scientific American".In 1992, he was given an associate professorship with a limited tenure, which became fully tenured in 1996.