Ethnic and racial discrimination in the hiring process is a common and documented problem. Scientists from different backgrounds and numerous countries have tried to measure the extent of this form of discrimination, mostly by using field experiments such as audit or correspondence tests. This paper will provide an overview of the literature on measuring discrimination in more general terms as well as reviewing the studies already conducted that focus on ethnic or racial discrimination in hiring. It will focus on how discrimination is defined in different disciplines, on the historical political context in which field experiments have emerged once anti-discrimination legislation was adopted in the US and the UK and how the technique was developed further over time. Methodological issues such as the difference between audit (i.e. in-person) and correspondence test (i.e. CV-based) will be addressed as well as the ethical and legal stumbling blocks researchers can encounter when conducting field experiments. It will be shown that today’s field experiments not only cover a wider group of countries, professions or minority groups, but also increasingly add more variables to the testing. Despite this variety in the research designs, this paper concludes that certain trends can be observed in all tests and that discrimination in hiring can be found in all countries where field experiments were conducted.