Visual communications design, which generally relates to design projects with specific communication objectives, includes most forms of graphic and digital design that have a commercial or an educational purpose. The effectiveness of such design projects rests on how well the embedded communications objectives are met from the perspective of the target audience. In advertising as in education, various post-campaign evaluation techniques are used to measure effectiveness. The challenge for designers is to create designs that are aesthetically appropriate and visually engaging for the target audience, but which are also functionally-legible and support the encoding of communication messages so that these are effectively decoded as intended. This is particularly important given that the effectiveness of visual communications is not guaranteed in the visually-cluttered environment of the 21st century. Of the design elements available to the designer of visual communications, colour and contrast play key roles in visual perception, and the strategic use of these can contribute to the effectiveness of visual communications design. Examining the roles that colour and contrast within the context of Gestalt theories of perception provides additional insight into the ways in which these design elements can be harnessed to improve the effectiveness of visual communications design. (c) 2013 Wiley Periodicals, Inc. Col Res Appl, 40, 85-92, 2015