Coordination polymers have been emerging as a topical research field in crystal engineering, solid-state chemistry, and materials science. Considering the wide occurrence of structural and compositional diversity during self-assembly and crystallization, supramolecular isomerism represents an indication of composition control and structure prediction. Actually, supramolecular isomerism is not just an obstacle or challenge, but also a good opportunity for developing novel materials and a better understanding of self-assembly and crystal growth. This critical review provides an overview of the developing knowledge, in the context of supramolecular isomerism, of the design, synthesis, and properties of coordination polymers (97 references).