In two parts, this thesis examined the perception of odour mixtures by humans. Several experiments were carried out and results shown. Part 1 established that peripheral interaction in the form of competition for transduction pathway resources is not of primary importance in determining the perceptual characteristics of odour mixtures. Other peripheral mechanisms, central factors and limitations in human cognitive processing would also appear to play an important role.Taking into account the temporal processing results found in Part 1, Part 2 sought to establish the capacity of humans to analyse odour mixtures in greater than two components in terms of the perceived order of components, and the identity of those components. Overall, the research demonstrated that two properties of simple binary odour mixtures, namely the temporal order and perceived strengths of components, are not primarily characterised by the transduction pathway those components putatively operate in human ORNs. / Doctor of Philosophy (PhD)