Abstract: In a method of making a printing plate for use in offset printing, a positive transparency of the design to be printed is first prepared in such a way that when the sensitive layer thereof is observed the design thereon is seen as right side out. This positive transparency is then mounted on a support provided with registration marks, with the sensitive layer of the transparency turned outwardly, and any errors in the transparency are corrected. The mounting is then used to contact-print a negative transparency on which the design is seen inside out when its sensitive layer is observed. Finally the design is formed on the printing plate employing the negative transparency, after any necessary re-touching of the latter.