Spot colors are reproduced with a combination of the primary printing inks cyan, magenta, yellow, black and at least one secondary printing ink red, green, blue. A first test form is printed with the primary printing inks and measured calorimetrically. Further test forms, in which one of the colored primary printing inks is replaced by a substantially complementary secondary printing ink, are printed and measured calorimetrically. An International Color Consortium (ICC) color profile is calculated from the measured data of each test form. For each spot color to be reproduced, the proportions of printing inks of the ICC color profile achieving the lowest deviation between the spot color and the reproduced color are determined. The printing ink combination belonging to that ICC profile is selected for the reproduction of the spot color. It is possible to reproduce as many spot colors as desired with four primary printing inks and a maximum of three secondary printing inks.