In MKII \sc switch to a different font but MKIV can just enable the "smcp" feature.
Adding "smcp=yes" doesn't work as option for \setmainfont because you can use \definfontfeature and overload the "default" set, the only valid options from \definefontfeature are "script", "expansion" and "protrusion".
[I'm using MKiV.] Ok, let's leave the small capitals with \sc alone, they work when I specify script=latin in setmainfont. Now, how would I activate the feature c2sc (small capitals from capitals)? It worked like this in the past, but does not anymore: \usemodule[simplefonts] \definefontfeature[c2sc][default][c2sc=yes] \setmainfont[Minion Pro][expansion=quality, protrusion=quality, script=latin] \starttext {\addff{c2sc} THIS TEXT SHOULD BE CONVERTED TO SMALL CAPS.} % does not result in small caps, what's wrong??? Compare: {\sc small caps} % does give small caps (therefore, not part of my question) \stoptext