Suppose you are the Employee Satisfaction Manager at a European multinational and you would like to conduct an employee satisfaction survey. More precisely, as you have heavily invested into an equal opportunities policy in the past year, you would like to find out if your investment is starting to pay off. In other words, if there are any differences in satisfaction between socio-demographic minority and majority groups. As a result, in order to be able to study this, you have to identify your minority groups. Consequently you have to ask your respondents/employees about some potentially sensitive topics such as sexual orientation, religious beliefs, … In other situations, subjects such as political preferences, income, various attitudes and behaviours, etc. are also considered to be sensitive issues.