Nine neutral dynamic metallosupramolecular polymers (metallodynamers) based on acyl hydrazone derived metal coordination centers (Co2+, Ni2+, Zn2+, and Cd2+) were generated through self‐assembly polymerization. These are linear coordination polymers with specific optical and mechanical properties. Monomer selection was found to take place in a mixture of subcomponents (carboxyaldehydes and bisacyl hydrazides) driven by hexacoordination to a specific metal ion. Most importantly, the metallodynamers were found to modify their constitution by exchanging and reshuffling their components with another metallodynamer through ligand exchange at the metal coordination site in solution as well as in the neat phase. As a result, the materials undergo remarkable changes in both their mechanical and optical properties. Copyright © 2008 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.