The aim of this proposed work is to complete our study of the behaviour of acetic acid/pyridine mixtures as a functionof composition, in order to fully characterise the changes in acetic acid clusters and oligomer chain formation acrossthe phase space. Such systems have been under continuous investigation from 1930s, through to thepresent day are of great current importance across disciplines ranging from the formation of protic ionic liquids through to structuring directing interactions in HIV-pepstatin complexes. The data to be collected here will target the key mixture compositions where major changes in bulk properties (viscosity/conductivity etc and responses toacceptor and donor number probes) are observed, providing a complete overview of the liquid structure across thewhole composition spectum.