Codes of ethics are one of the most widespread instruments of (self-)regulation for journalistic activity, pointing out the best professional practices and ethical standards to be followed and the need to allow some kind of scrutiny by the public. Such codes have different names, scope, authorship, range of action, and enforcement capacity, as can be seen in the various reports of the 18 countries participating in the 2021 Media for Democracy Monitor (MDM) research project. In this chapter, an historical overview of the evolution of journalistic codes of ethics in different national media contexts is given, as well as an analysis of the cornerstones such codes are built upon in various countries. We discuss the specific virtues and shortcomings of such codes, with a particular emphasis on the new challenges brought by the digital media environment. The role played by codes of ethics, compared with the laws that regulate media, is also addressed.