A list of constitutional units (CU) used for naming polymers according to IUPAC nomenclature rules is provided. This list contains CUs of commercial and well-known polymers as well as CUs which have been used in polymer-nomenclature-related IUPAC documents. A preferred name is provided for each constitutional unit. Other acceptable names, and names which must not be used because they are outdated or incorrect although they may have been correct in the past or in a different context are also listed. A second table contains names of common polymers: structure-based, source-based, retained traditional polymer names and not acceptable names, again because they are outdated or incorrect. These tables supersede similar tables and names in previous documents. The rules given in those documents are still valid but names of constitutional units should be checked for agreement with the present document. The preferred names of constitutional units in Table 1 should be used in structure-based names of regular and irregular polymers.