The advancements in experimental methods and modeling techniques for determining multiple conformational states of biomolecules necessitate improved methods for representing and archiving information about conformations in dynamic equilibrium. This can be challenging, as definitions of alternative conformational "states" depend on the timescale of the experimental data and/or the modeling methods used. Apart from the well-known Protein Data Bank (PDB) and Nucleic Acid Database (NDB), several other databases (ACMS, CoDNaS, D3PM, GLOCON, and MultiComp) primarily store and annotate data on alternative conformations obtained from diverse crystal structures, as reported in the PDB. These databases, along with other important structural databases that primarily archive single-state models but can also provide data about multiple conformational states, are listed in Table , along with their URLs.