The aim of this paper is to illustrate the use of gloss effects for security printing. These gloss effects can be produced using pigmented ink jet inks. The main reason for using this type of artifact for security printing is that the effects can be made invisible to typical desktop scanners while still remaining readable by the human eye and machine reading systems. The two gloss effects investigated are differential gloss and gloss color. In both cases, methods of visualizing and measuring these are considered with examples. The paper continues by giving examples of some of the variables that can be used to make this a secure system and concludes with a series of photomicrographs examining the root cause of these effects.