This article addresses the impact of different sampling procedures on realised sample quality in the case of probability samples. This impact was expected to result from varying degrees of freedom on the part of interviewers to interview easily available or cooperative individuals (thus producing substitutions). The analysis was conducted in a cross-cultural context using data from the first four rounds of the European Social Survey (ESS). Substitutions are measured as deviations from a 50/50 gender ratio in subsamples with heterosexual couples. Significant deviations were found in numerous countries of the ESS. They were also found to be lowest in cases of samples with official registers of residents as sample frame (individual person register samples) if one partner was more difficult to contact than the other. This scope of substitutions did not differ across the ESS rounds and it was weakly correlated with payment and control procedures. It can be concluded from the results that individual person register samples are associated with higher sample quality.