In the 1980s and 1990s in the Netherlands, as a reaction to the growing number of non-Christian pupils at Christian schools, religious education and religious development became issues for debate. At some schools, it was the exclusiveness of the Christian tradition that dominated, and at others it was the inclusiveness. Another group specialised in inter-religious dialogue. Our research studied the religious development of pupils from two primary schools. One is the first and only inter-religious primary school in the Netherlands, the Juliana van Stolberg primary school. The other is a Christian school, the Prinses Margriet primary school that educates pupils exclusively in the Christian tradition. The research questions focussed on the development of the "God" concept of children confronted with stories from different religious traditions. The "God" concept is seen in our research as a concept that develops in an inductive way from the data. This way of conceptualising "development" is coined as the prospective perspective on development. The results of this comparative research led to the tentative conclusion that pupils in our research population who were involved in inter-religious learning, demonstrate explorative behaviour concerning their own religion and that of others. Their "God" concept shows hybrid characteristics. These pupils are rooted in their own tradition, and at the same time they are "on the move". This offers points of departure for the development of citizens articulating their commitments and turning imminent conflicts into inter-religious encounters. (Contains 12 notes.)