Short answer
The Salesforce sharing model decides which records each user can see and edit. It starts with organization-wide defaults (OWD), then opens access through the role hierarchy, sharing rules, public groups, teams and manual sharing. It is how firms enforce need-to-know access to client data.
Salesforce Sharing Model explained
Organization-wide defaults set the most restrictive baseline for each object, such as Private or Public Read Only. The role hierarchy lets managers see their teams' records. Sharing rules open access to groups based on ownership or criteria, public groups bundle users for sharing, and account or opportunity teams grant access record by record. Financial Services Cloud adds compliant data sharing for finer control over who sees financial accounts.
Getting this right matters most in regulated firms, where advisors should see only their own clients and some teams must be walled off from others.
How Vantage Point helps: we design sharing models for wealth, banking and insurance teams and document them so compliance can sign off.
Frequently asked questions
What are public groups in Salesforce?
Public groups are named sets of users, roles or other groups that you can share records with in one step, instead of sharing with each user individually.
Can reps be prevented from seeing each other's leads?
Yes. Set the Lead org-wide default to Private and grant extra access only through roles or sharing rules where it is needed.