The fungal hydrophobins are small proteins that are able to spontaneously self-assemble into amphipathic monolayers at hydrophobic:hydrophilic interfaces. These protein monolayers can reverse the wettability of a surface, making them suitable for increasing the biocompatibility of many hydrophobic nanomaterials. One subgroup of this family, the class I hydrophobins, forms monolayers that are composed of extremely robust amyloid-like fibrils, called rodlets. Here we describe protocols for the production and purification of recombinant hydrophobins and oxidative refolding to a biologically active, soluble, monomeric form. We describe methods to trigger self-assembly into the fibrillar rodlet state and techniques to characterize the physicochemical properties of the polymeric forms.