This chapter defines localization and explains its relation to advertising. Localization roughly involves three major fields: multilingual translation of complex technical texts, software localization, and audiovisual translation (subtitling, games, etc.). It involves a considerable amount of computer power but it is much more than the mere application of technical skills: it takes elements from cultural studies and marketing strategies as well. By definition, localization aims at a local target audience. It aims to domesticate the source product and by doing so conceal the “otherness” of that product. When promoted by advertising campaigns informed by local attitudes and cultures, a particular product can be perceived in completely different ways by consumers in different markets. The chapter discusses localization as a business model, and also pays attention to its specific relation to internationalization.