Abstract: For applying a security code to an article, such as a cheque guarantee card, credit card, identity card or component of a motor or machine, use is made of a hologram or kinegram wherein personification or identification symbols, letters, numerals or figures are or will be cut out by burning-in using a laser beam, said hologram or kinegram being affixed to an underlying hologram or kinegram which is affixed to the article directly or via one or more holograms or kinegrams, the various features being such that the optical effect of an underlying hologram or kinegram is visible through the cut-out symbols.