Freire used very specific materials in culture circles to support an empowering process that allowed learners to define the content and outcome of their own learning. However, the materials themselves were carefully crafted and developed by Freire and his co-workers. This article focuses on an extension of Freire's problem-posing educational methods to include participant involvement in the development and production of their own learning materials. Four linked case examples, one in literacy and three in health education, illustrate the process of participatory materials development and we discuss some issues for facilitators and learners. The production process can be an empowering experience and the product stands as testimony to the participants as self-conscious agents and critical thinkers capable of transforming their world. The resultant materials, geared to a particular locale and reflective of the people and language in the community, can provide a powerful model for those who may not have been involved in the process, but who can identify with the friends and neighbors who developed the materials. Participatory materials development is suggested as a supplement to problem-posing educational experiences and is particularly well suited for community programs.