Person custom fields allow you to assign an existing user from your organization as a value in your custom field. Note that this field can only be used as a single-select dropdown!
Person custom fields are available on the Ultimate subscription plan.
1) Adding a Person Custom Field
To add a person custom field either:
1) Go to Settings > Custom Fields:
Select the object you want to add it for (e.g. Bookings, Budgets, Companies, Deals, etc.) and click on "Add new custom field".
2) Navigate to Settings > Employee fields:
If you are adding the field for your employees and contractors, open the Employee fields, and click on Add new field.
2) Selecting the Person Field
From the menu, select the Person field.
3) Name and Describe the Field
Give the custom field a name and description and click "Create field".
Here is an example of how the "Main point of contact" custom field from the screenshots above looks like when created and added to the Companies view in CRM > Companies, for instance.