Jack Vance 1st Ed The Cadwal Chronicles Araminta Station Ecce & Old Earth Throy

FROM WIKIPEDIA:

The Cadwal Chronicles are a trilogy of science fiction novels by American writer Jack Vance set in his Gaean Reach fictional universe. The three novels are called Araminta Station (1987), Ecce and Old Earth (1991) and Throy (1992).

Cadwal is a planet discovered by an explorer who is a member of the "Naturalist Society of Earth". The society decides to maintain Cadwal as a nature preserve and sets up a Conservancy based on a Charter. The Charter forbids mining and other exploitation, and permits strictly limited settlement. Only six "Agents", each in charge of a bureau with a staff of 20 men and 20 women, are allowed to reside permanently on the planet to enforce the Charter, although tourists are allowed in specially designed lodges, overlooking sites of natural beauty and interest.

From the earliest days, the Agents recruited relatives and close associates for their staffs, but as their numbers eventually exceeded the Charter limits, the excess remained on Cadwal as "collaterals" under the transparent fiction of being "temporary" labor. At their 16th birthday, each person learns their "index number", indicating their genealogical rank. A person whose index number is 20 or less upon their 21st birthday is granted Agency status; all others become lesser-status collaterals. Many collaterals choose to leave Cadwal to seek their fortune elsewhere in the Gaean Reach. Thus, the society of Cadwal is a highly stratified aristocracy, where success depends on birth as much as aptitude.

An additional group of temporary laborers is tolerated on the planet: the "Yips", who are described as the "descendants of runaway servants, illegal immigrants and others." For them, the Charter is more strictly enforced compared to the collaterals. They are allowed six-month work permits at Araminta Station, the main settlement, an enclave of 100 square miles (260 km2) on Deucas, the most hospitable of Cadwal's three continents. When a permit expires, the Yip is returned to tiny, greatly overcrowded Lutwen Atoll, informally called Yipton. The Yips vastly outnumber the legitimate residents and are only prevented from settling Deucas by the superior firepower of Bureau B.