Hydrazone‐based systems have been, and continue to be, widely studied in the field of supramolecular chemistry due to the chemical versatility of their triatomic C=N‐N structure, whose amino nitrogen commonly bears a methyl group or a hydrogen atom. Herein we review the conformational, configurational, and constitutional dynamics of these systems, focusing on the particularly important role of the N−H group of the hydrazone framework in each of those processes observed in molecular and supramolecular systems published in recent decades. Due to the enormous diversity of supramolecular architectures and molecular entities, the most representative synthetic methodologies to obtain them are described.