The theme I want to address is the relationship between property rights and economic development. Property rights and land rights in particular are important elements in any country's social, economic and political organization. Concepts, rules, principles and procedures lay down which social entities may legitimately control and exploit resources and who takes what profit from such exploitation. They lay down the conditions under which such resources may be appropriated, acquired, inherited or transferred. The distribution of property rights to natural resources is an important indicator of the level of welfare or poverty of a nation's population, of economic differentiation or social and economic equity. Any major attempt - by governments, social groups or social movements - to change the ways in which property is used or distributed therefore is likely to involve and require the introduction of new rights through legislative action and the implementation of legislation. Because new property rights regimes are generally introduced via new law, assumptions about the relation between law and development also enter these debates. Law, especially new law, is regarded and used as an important instrument of policy making to change social and economic conditions. Different sets of assumptions relate specific types of property rights to specific forms of economic development and social justice, and, more recently, also to more or less sustainable use and management of natural resources (F. von Benda-Beckmann 2001). Law, and the new rights it creates, is employed as a means of "social engineering" (see Okoth-Ogendo 1984, Hitchcock 1980, Coldham 1978). One expects that the behaviour of people will follow the new law and rights, and by doing so contribute to new economic and social conditions. So law is seen a causal force. Sometimes it is indeed used as a "magic charm" to bring about economic development (F. von Benda-Beckmann 1989). The earlier law, the one to be replaced, is also seen in the context of these causal assumption. It then becomes the main cause or reason for the unsatisfactory social and economic conditions, the “scape goat” for underdevelopment. However, when we think about the creation of a new property rights regime we cannot expect that people's behaviour would correspond immediately with the legal regulations laid down in the new property law, for instance a land right reform. The effects will always be influenced by the previously existing legal constellation, and by the constellation of rights which existed before the introduction of the new law. Moreover, the consequences will differ locally, because the local forms of social, economic and also legal organizations, the 'semi-autonomous fields' (Moore 1978), into which the new regulation comes, differ. One therefore must carefully assess the probable consequences which might be connected with the introduction to the new law.