The inability to predict the pharmacology and toxicology of drug candidates in preclinical studies has led to the decline in the number of new drugs which make it to market and the rise in cost associated with drug development. Identifying molecular interactions associated with therapeutic and toxic drug effects early in development is a top priority. Traditional mechanism elucidation strategies are narrow, often focusing on the identification of solely the molecular target. Methods which can offer additional insight into wide-ranging molecular interactions required for drug effect and the biochemical consequences of these interactions are in demand. Genomic strategies have made impressive advances in defining a more global view of drug action and are expected to increasingly be used as a complimentary tool in drug discovery and development.