Although evaluation of income inequality has been the subject of many studies, there are questions that remain to be answered. In regard to the structural position thesis, the reflection thesis and dominant ideology thesis, this article examines how much income inequality people will accept before deciding that the disparity is too large and how societal differences can be explained adequately. For this purpose, the attitudes of about 35,000 respondents in 30 countries are investigated. A multi-level analysis is carried out using data from the ISSP survey 'Social Inequality III' of 1999. At the societal level, both socio-economic and cultural characteristics are considered. While much research places emphasis on dominant ideologies, this analysis in addition attempts to grasp these ideologies by aggregating individual beliefs. It is shown that societal differences are well explained by ideologies, but that socio-economic characteristics are important as well. At the micro-level, several individual characteristics are considered. Among other things, people at the top of the vertical axis are less critical than those at the bottom. There are also substantial differences between societies in regard to how much inequality in income ratio will be accepted. Thus, people not only accept different amounts of income, they even have different preferences about which ratio is just.