In most pharmaceutical and biotechnology companies, high throughput screening (HTS) is a central function in the drug-discovery process. This has resulted from the fact that there are increasing numbers of validated therapeutic targets being discovered through advances in human genomics, and increasing numbers of chemical compounds being produced through high-throughput chemistry initiatives. Many large companies study 100 targets or more each year, and in order to progress these targets, lead compounds must be found. Increasingly, pharmaceutical companies are relying on HTS as the primary engine driving lead discovery.