I have tried style={\switchtobodyfont[karat]} and it works. Now how to switch to a different size without going through: \setupbodyfont[karat] \definefont[MyPartFont][SansBold at 24pt] \setuphead[part][style=\MyPartFont] The problem i see here is that i have to go through \setupbodyfont[karat] and that i can't say something like: \definefont[MyPartFont][karat at 24pt] Lets say i have 5 fonts in my document i only want to say \setupbodyfont[MyMainFont] once, then i should have other mecanisms for switching properly to other fonts at different sizes. Why does \definefont maps only from Sans, Serif, SansBold etc. ? This is quit fastidious, cause for this to work we have to use \setupbodyfont first and follow the steps above. I may be missing something out there .. Many thanks. Dirar.