Change Default Relationships

[mbriney]

Is it possible to change the relationship type for the default modules?

For example, Instead of Organizations having a one-to-many relationship with Events, I would prefer that it have a many-to-many relationship.

[rafael.q.g@hotmail.com]

Yes it is possible!
You could try to start taking a look on files under "metadata" folde, which contains all deafult relationships defined.

Finding the desired file (for the relationship of your interest) you could change the relationship type there.
After save that, and run a repair/rebuild. (Maybe you have to change some layouts (detail/edit views) also).

Once it is working, move the changed file to custom/metadata folder, this way your change will be safe upgrade.