The Diels-Alder reaction has both enabled and shaped the art and science of total synthesis over the last few decades to an extent which, arguably, has yet to be eclipsed by any other transformation in the current synthetic repertoire. With myriad applications of this magnificent pericyclic reaction, often as a crucial element in elegant and programmed cascade sequences facilitating complex molecule construction, this cycloaddition has afforded numerous and unparalleled solutions to a diverse range of synthetic puzzles provided by nature in the form of natural products. After numerous near-discoveries of the [4+2] cycloaddition reaction by several luminaries in the field of organic chemistry during the early part of the 20th century, the keen insight of Professor Otto Diels and his student, Kurt Alder, in properly identifying the products arising from the reaction of cyclopentadiene with quinone denotes a historic event in the field of chemistry for which these two individuals were rewarded with the Nobel Prize and the reaction that immoratlised their names.