Today with the rising cost of petroleum base products, the environmental concerns, and the rarefaction of fossil raw materials there is a renewed interest in renewable resources. Triglycerides, fatty acids and esters derived from vegetable oils are very interesting renewable susbstances. Indeed, fatty acids have a long tradition as monomers in coating resins or as lubricants. They have been used as received from the plants as air-drying linseed oils or as parts of resins such as alkyds. All these fatty substances can be chemically modified. The thiol-ene coupling has been considered recently as a promising mechanism to functionalize the double bonds of fatty acids.