The drying behaviour of thin films is a ubiquitous phenomena, important to a multitude of industries and applications. When a solid phase is present, the added complexity leads to a variety of possible patterning behaviours. This thesis focuses on thin films that crack during drying. The physical underpinning of the varying crack morphologies that occur is only partly understood and a hierarchy of models are derived to account for the evaporative process. We distinguish three regimes of interest; structure development, evolution and fracture formation. Each process is isolated to understand the intricacies that occur during drying. Structure formation is modelled by a structure parameter, inspired by the study of thixotropy. The initiation and propagation of cracks in drying gels are modelled with a damage parameter, whereby discrete cracks are homogenised into a continuous field. The naturally occurring length scales allow for dimension reduction by the lubrication approximation. At leading order in the aspect ratio, ε = H/L, the solid fraction is found to be enslaved to the evolution of the free surface. Increased evaporation at the contact line drives drying fronts, regions of increased solid fraction which invade into the bulk. Evaporation-driven compression induce tensile stresses within the plane, resulting in cracks initiating at the contact line. Similar to experimental evidence, cracking occurs before 20% of the droplet mass has evaporated off, further promoted by front formation. In addition, the crack morphologies display an order-to-disorder transition as drying fronts become stronger. During experiments, increased evaporation at the contact line results in the formation of a gelled annulus, surrounding a thinner gelled nucleus. An alternative model is derived, where we consider both regions independently, finding good agreement with experiments. In particular, the formation of radial cracks in the outer rim, alongside discrete or cellular morphologies within the bulk dependent upon effective parameters.