Skin, external surface, coating… Those are words strictly linked to the concept of appearance, which means to be watched, to show, and sometimes to seem: a comparison between being and appearing. From a design point of view, the surface coating is, mainly, an esthetical choice. Nevertheless, sometimes that element has been due to other reasons. During the First World War, painting warships with the dazzle technique allowed them to “hide” from the enemy: the shapes and colours applied to hulls allowed them to appear in different sizes or positions compared to the actual real one. In that case, the skin assumed a vital defensive role. Even if most yachts today do not shine with peculiar external surfaces – if we closed our eyes we could imagine hulls in neutral colours, generally in one or two tones – skin however is a project element with significant potential. Ivana Porfiri commissioned Jeff Koons, acclaimed contemporary artist, to finish the external coat of the Guilty. The skin highlights shapes and formal choices of hull and superstructure, and also takes forward the link between art and yacht design, explicit by the display of art in the interiors. Another example of designed skin is LAP-1 by Francesco Paszkowski Design. Here the external coating was designed with camouflage with shades of blue, a symbolic colour for the Baglietto shipyard, responsible for building the yacht. Finally, browsing the most significant projects, the paper aims to analyse the design and use of external coatings of yachts. The skin project in a nautical context is today mainly linked to aesthetic reasons. Nevertheless, also thanks to the use of new materials, innovative painting, and covering techniques, new possibilities for skin design are envisaged. External coating, colours, textures and hull finishing could meet different and new needs in the energy and environmental field.