Best Practices Of Creating Contact Sharing Rules in Salesforce?

Adding some more points:

Account Org-Wide Default must be set to at least “Public Read Only” in order to set the Contact Org-Wide Default to “Public Read/Write”.
– To share ALL contacts in the system with a group of users or a specific role, create a sharing rule that uses the “All Internal Users” (or “Entire Organization”) public group as the owned by option.
– Use “Roles and Subordinates” over “Roles” where possible to minimize the number of sharing rules.

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