Harpers are members of a secret society dedicated to holding back evil, preserving knowledge, and maintaining the balance between civilization and the wild. Harpers learn arcane spells and many skills to help them in their duties of espionage, stealth and reporting information. Many Harpers are bards, but by no means all. Ranger, rogue, sorcerer and wizard are common vocations for Harpers, as these classes tend to have versatility and mobility. All have some skill at manipulating others, a resistance to outside mental influences, acute abilities of perception, and a talent for solving problems.

Not all Harpers are members of the Harper prestige class, and rank within the organization does not depend upon a character?s level in this or any other class. However, most of the higher-ranked Harpers have at least one level in the Harper prestige class.​