Two-components methoxymethyl melamine/isocyanate and three-components methoxymethyl melamine/isocyanate/polyol coating systems were studied. Methoxymethyl melamine was shown to react with isocyanate groups through the carbocation formed by splitting within the methoxymethyl group. In three-components systems, methoxymethyl melamine/polyol and methoxymethyl melamine/isocyanate reactions appear to occur, but not isocyanate/polyol reactions. This was ascribed to the release from the methoxymethyl melamine/polyol reaction of methanol which reacts more rapidly than the polyol with the isocyanate group. A blocked isocyanate was then used whereby the methoxymethyl melamine reacts at an earlier stage and urethane formation is delayed. Introducing the blocked isocyanate, however, required significant increases in cure temperature for the isocyanate/polyol reaction, narrowing the cure temperature window of the system.