The drying of industrially relevant latex dispersions designed for use as pressure-sensitive adhesives (PSAs) was followed using Forster resonance energy transfer (FRET) and scattering intensity as indicators for the progress of film formation. FRET and scattering intensity report the state of polymer interdiffusion and of particle deformation, respectively. Because the exciting UV-radiation only penetrated a few micrometers deep into the film, FRET measurements undertaken from the top and the bottom yielded different results. The combination of the two evidenced skin formation. Particle deformation occurs in two steps. There is a significant, but incomplete, decrease in turbidity because of skin formation. Only after the drying front has propagated to the substrate, the top layer turns fully clear. This second step is interpreted as coalescence, meaning the breakup of lamellae separating particles. Coalescence is followed by a sharp increase in interdiffusion. Further aspects studied included crosslinking, hydroplasticization, and tackifying resins.