Building a science on the foundations of practitioners' experimentation was one of Donald Schön's abiding interests. This paper outlines a method of reflective practice research on which this kind of science can be built. Its basic elements are: (1) A focus on the "sense" practitioners make of their situations. This allows for a much richer explication of practitioners' understanding. (2) Formally differentiating between kinds of reflective thinking to demonstrate rigorous reliance on our practice, as experienced, as we reflect. (3) Use of a non-standard logic and a distinctive grammar in describing the "sense" we make of our practice situations, as this enables a much more faithful rendering in models and theories of our sense of orientation. (4) A method of combining these in an experimental practice that enables models of practice traditions to evolve, taking in insights from innovative practice, and experiences from diverse cases.