R> trellis.par.set(superpose.symbol=list(pch=c(1, 2))) Warning message: Note: The default device has been opened to honour attempt to modify trellis settings in: trellis.par.set(superpose.symbol = list(pch = c(1, 2))) R> xyplot(csoa~it|sex*agegp,data=tinting,groups=target,auto.key=list(space="right")) Thanks that did it!