Contact Subtypes is a convenient place to manage, update and edit your contact types.
When creating or updating a contact, you are able to select a type of contact:
From this screen, like with labels, you can quickly select a type, or if the type does not exist, you can enter the name of a new type and select enter.
As you type in this text area, potential matches will appear. If none of the options lines up with what you need, you can click your text to create the new entry.
Here I've started typing "Adjuster" as I type, the list is filtered in realtime displaying potential matches:
Once created, "Adjuster" will be an option from the dropdown and available for any future contacts:
Being able to do this on the fly from the contact edit screen makes it easy to quickly maintain and update your list of contact types. But, with great power comes great opportunity for duplicate entries. So, the contact types customization setting gives you a centralized place to maintain your list in a tidy way.
You can navigate to contact subtypes from Settings > Customization > Contact Subtypes
From here you can quickly add your most commonly used contact subtypes, and make sure any duplicates or misspellings are corrected.
This list will also inform the related contact type on a matter. While a contact may have a type associated with that contact (for example, a doctor may always be a doctor) this can be replaced on a matter basis. For example, if that doctor is actually the referral source for a case you might want to add them as a related contact for the referral source, as a doctor, or even entries for both. Making the choice on the related contact section of a matter will not update the subtype associated with the contact. However, the related contact type will be what is used to generate documents and decide what contacts are available for a specific merged document.