Crosslinking reactions in latex and alkyd systems offer an attractive way to achieve film formation at low temperatures while also achieving a final hard coating. There is a strong need for techniques to characterise the extent of crosslinking as a function of time and depth in this type of coating. Here magnetic resonance imaging (MRI) (using a magnet specifically designed for coatings) and a quartz crystal microbalance with energy dissipation are both used as non-invasive techniques for this purpose. The crosslinking in alkyd films containing a cobalt drier is found to be non-uniform with depth. In a latex, crosslinking depth profiles are likewise non-uniform, most likely as a result of oxygen inhibition of the initiator