Joseph Novak, the inventor of concept maps, explains in this interview how that idea was born thirty years ago. As a student he developed a passion for education, trying to find better ways to educate people and help them "learn how to learn". Concept maps can profitably be used to represent knowledge in every field of study: they help students to construct new learning and are also useful for teachers to discover possible misconceptions in the students' own construction. Novak discusses the advantages of meaningful learning and the foundations of his theory of education based on "human constructivism" and he summarizes it in a concept map. He also explains why concept maps are a useful tool for corporations, too.