Custom matter fields help you push the boundaries of your Lawcus account, allowing you to solicit for and get extra data about matters. So, custom fields are the way to go if there's a data field important to your practice area but is missing by default on a matter data form.
Creating a custom field for matters
To create as many matter custom fields as you want:
Click user avatar on top-right and click Settings
Go to the Firm Settings section and click Custom fields
Navigate to the Matter Custom Fields tab and click Add
Input the new custom field title in the Name field, choose the type of field it would be
Check the Default checkbox to make the custom field always appear and/or the Required checkbox, then click Create Custom Field