The representation of a person's understanding of a domain of knowledge in a form that others can easily comprehend is fundamental for learning, knowledge preservation, and organization of information. Researchers at IHMC have developed and continue to enhance CmapTools, a software toolkit that allows users of all ages to express and share their understanding about a topic in the form of concept maps. We use CmapTools as a basis to carry out research on how to organize information in ways that provide more effective browsing and searching; as a tool during knowledge elicitation and as a mechanism for knowledge preservation in organizations; and as a tool to facilitate meaningful learning for students of all ages. To support the worldwide adoption of CmapTools, two websites are being developed to (a) support the community of concept mappers and provide a site for anybody to learn about concept mapping (Cmappers.net), and (b) support concept map-based collaborative projects among students from different schools (LiveMappers).