Bregan D'aerthe was primarily a mercenary and mercantile band which became a pirate group after the portal to Shedaklah was opened in the Underdark. Members, both individuals and the band as a whole, were usually available for hire to the highest bidder. Bregan D'aerthe was involved in most conflicts in Menzoberranzan in one way or another. The band expanded to trade goods from the surface to Menzoberranzan and the Underdark. For example, they traded Netherese artifacts to Menzoberranzan via Luskan.
Bregan D'aerthe was also an information broker, willing to provide information for both sides of a conflict—for the right price. Its contacts reached even as far as the Unknown city of Blingdenstone.
Bregan D'aerthe had a reputation that normally allowed its agents to skip lines. Its members were given "credit" — often they didn't need to pay because of the threat of retaliation from Bregan D'aerthe.