Attempts to undertake comparative cross-national and cross-cultural research face many challenges. In the case of the Children’s Worlds project the diversity of the countries participating in the project is in many ways a strength – generating a unique set of data. In addition, the project has other strengths in terms of the size of the data set and the approaches taken to piloting, sample design and ethics as described in Chapter 2. On the other hand the diversity of the sample of countries also raises substantial issues to consider both in terms of methodological and analytical approaches.