Motivations: What is Constraint Theory and why is it important?- The Four-fold way: How to Perceive Complex Mathematical Models and Well-Posed Problems -- General Results: From Protomath to Math to Metamath -- Regular Relations: Searching for the Kernels of Constraint -- Discrete and Interval Relations: The Diminished Utility of Metamodels -- The Logical Structure of Constraint: Theory A Compac…