Discrimination is a key obstacle to the full integration of immigrants and their offspring into the labour market and the society as a whole. This chapter provides an overview of discrimination against immigrants and their children in OECD countries – its measurement, incidence and policy solutions – on the basis of the empirical literature and policy practices.The actual prevalence of discrimination is difficult to assess, since the disadvantage of immigrants and their offspring in many domains of public life may be attributable to many other factors – both observed and non-observed – than ethnic origin itself. Testing studies which try to isolate the effect of discrimination in hiring suggest that it is not uncommon for immigrants and their offspring to have to send more than twice as many applications to get invited to a job interview than persons without a migration background who have an otherwise equivalent CV.Most OECD countries have taken measures to combat discrimination, although the scale and scope of the measures varies widely. Much of the effect of most policy measures against discrimination appears to stem rather from raising awareness about the issue than from any direct influence which they may have on preventing discrimination.