RDA contains a number of guidelines and instructions that are marked as alternatives, options (optional additions, optional omissions), and exceptions. Each of these is clearly identified by an italicized label, which in the RDA Toolkit appears in green color in the instruction (alternative, optional addition, optional omission, exception). A green vertical bar also appears in the left margin next of an alternative, optional, or exceptional instruction in RDA Toolkit. These allow individual libraries or cataloging agencies to make decisions based on individual considerations in cases where two or more provisions are equally valid. Guidelines for alternatives and options are provided in RDA rule 0.8, and instructions for applying exceptions is at RDA 0.9 of chapter 0. ... ... ...