It is widely assumed that children, especially younger children and those in poorer circumstances, are unreliable informants of parental occupation and related characteristics, thereby precluding the measurement of social class in much research involving children. In a comparison of reports of parental economic activity and occupation by 11 year olds and their parents in the West of Scotland 11 to 16 Study, the assumption is found to be unwarranted. This school-based study, which used a ‘mini-interview’ to question children about parental characteristics, found lower levels of missing data among children compared to parents and ‘(very) good’ levels of agreement (as indicated by the Kappa statistic) about both economic activity and occupation. These results, which were similar for boys and girls and those in different material and family circumstances, also suggest that children may sometimes provide more valid reports than parents themselves. Under particular fieldwork conditions, therefore, children as young as 11 from diverse social backgrounds can provide reliable, and possibly very valid, reports of parental socio-economic characteristics. With few additional resources, most studies of child only informants could reproduce that study's fieldwork procedures to obtain good data on social class.