Currently there is no way other than to build a new table and list page to represent a many-to-many relationship as evidence by how Job Responsibilities are currently added to Person Contacts. This is both significant extra work and provides a sub-optimal user experience compared with best practice label/tagging offered in other web applications.

Can we provide a new field type or properties that support this type of relationship (with underlying table plumbing generated transparently) and also a corresponding visual user interface representation that works across web, mobile, tablet, etc.