This white paper will discuss the features of Complex Programmable Logic Devices (CPLDs) in general, and CoolRunner-II devices specifically, that lend validity to some of these claims. It will cover the basics of tamper resistance as well as detail some of the more interesting data-attack methods. Describing the technical value of CoolRunner-II CPLDs in hindering these attacks, it will conclude by summarizing the degree of safety provided by the use of CoolRunner-II devices and outlining additional defensive steps that can help to ensure data security.