FinFolio has had the ability to allow adding custom fields to households, clients, accounts and securities. You can build extensions onto the edit screens that show these fields. You can show these fields on screens and custom dashboards. You can import into these fields from spreadsheets and other external sources.
Custom fields are powerful and let you customize FinFolio for use with your firm. They add a CRM element to usage, allowing you to track ancillary information that is important to your firm. Do you cater to veterans? Add military information. Do you sell 401K's to airline pilots? Add a retirement date field so you know when to pitch them on expanding your service.