Modern drug discovery, the process aiming at the generation of novel drugs, starts with the identification of a given molecular target, e .g. a DNA, RNA, or protein molecule within the human body or within a human pathogen that will then be targeted for the identification of "interfering entities", usually small organic molecules. The identification of compounds that show potent and selective activity against the chosen molecular targets requires the combined expertise of biochemists, pharmacologists and medicinal chemists who will work together to improve the ability of said compounds to affect that target function both in vitro and most importantly in vivo.