The olfactory sense is difficult to measure. Measurement of olfaction covers at least four separate paradigms, all of which require separate methodologies to analyse, and all of which are subject to a litany of known and unknown variables. As a result, devices used to measure olfaction, olfactometers, have progressively developed variations and sophistication. Despite their comparative infancy, olfactometers have been established across a broad spectrum of disciplines; primarily psychology, neuroscience, biology, food science, and environmental engineering. While these separate disciplines have all shown a need for olfactometer technology, there is also very little cross-disciplinary information sharing. This review is a précis of modern olfactometer techniques across research disciplines in order to collate their growing complexity and utility.