Serfdom was pervasive in Tibet and all laymen with the exception of a few hundred aristocratic families were hereditary serfs, tied to a lord through an estate. Nonetheless, the Tibetan social system was not rigid and closed. There was a significant modicum of mobility although mobility only between various serf substatuses.
The article examines the nature of the major serf sub-statuses and particularly focuses on the status of “human lease.” In a sense analagous to leasing land, the human-lease serf leased his personal freedom of movement and livelihood from his lord and was no longer obligated to work his lord's estate. But he was still a serf. He still had to pay an annual “lease” fee to his lord, and moreover, this linkage to his lord was still passed on to his offspring. The most striking feature of traditional Tibetan social structure emerges not as rigidity or flexibility but rather as the incorporation of a significant potential for mobility with a matrix of pervasive and hereditary serfdom. The institution of human lease reinforced the ideology underlying the estate system while providing the system the flexibility it needed to adapt to changing political and economic conditions.