Current Build
Patient Administration Work GroupMaturity Level: N/ABallot Status: Informative
Defines common extensions used with or related to the Organization resource
organization-periodperiod :

The date range that this organization should be considered available.

organization-preferredContactpreferredContact :

This Contact is the preferred contact at this organization for the purpose of the contact

There can be multiple contacts on an Organizations record with this value set to true, but these should all have different purpose values.