Information about colour psychology and colour therapy abounds in popular culture. Articles found in mass media as well as a plethora of Internet websites are often devoted to colour and a range of psychological, biological, and behavioral effects. The information available, which varies from scant summaries with catchy titles to lengthy and comprehensive discussions, is often presented in an authoritative manner exhorting the reader to believe a range of claims such as red is physically stimulating and arousing and blue is calming, relaxing and healing. However, empirical evidence or evidence of any nature is only rarely cited and, when it is, it's often in reference to findings that are inappropriately generalized or out-of-date and superseded. This article discusses a range of colour psychology and colour therapy claims found in popular culture and notes the similarities between these claims and the writings of early theorists such as Birren, Goldstein, Gerard and Luscher. While these authors have a valid if somewhat dated place in the literature on colour, there are a number of key reasons to be wary of colour psychology and colour therapy claims made in popular culture. These reasons are discussed in some detail and provide compelling support for applying the caveat emptor principle to colour psychology and colour therapy claims found in nonacademic sources. (C) 2010 Wiley Periodicals, Inc. Col Res Appl, 36, 229 - 234, 2011; Published online 29 April 2010 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/col.20597