Equity has been recognized as one of the driving principles of many health systems in the world. In Latin America, Chile has led the explicit inclusion of equity in their health policies, which is reflected in its recent health reform. On the other hand, Chile faces the challenge of defining and implementing a policy for health technology assessment (HTA), which should be consistent with the equity principles that underlie the Chilean national health system. This paper reviews the equity concept emphasizing the relevance of socioeconomic inequalities. Furthermore, it examines how international HTA agencies have explicitly included this element in the evaluation and decision processes. It presents the English case, which highlights the elements of procedural justice rather than adopting a normative position regarding equity. Finally, it examines the methods that have been developed aiming to make explicit consideration of equity in HTA. It concludes that the methodological development to incorporate equity elements with empirical basis is recent and limited. The consideration of equity is, in most of the cases, left to the instances of deliberative participation.