This thesis deals with the context of the accession of Romania to the EU and more widely with thesecond post-communist decade (2000-2010) in which we analyse the evolution of Romanian agricultural structures. In this context, the question of the main factors of structural changes arised as well as the role of supportive public policies. Firstly, the theoretical framework based on development economics and historical institutional economics is built. It then enables in a first partthe analysis of the embeddedness of Romanian agricultural sector within its social context. In thispart, we are also define and characterize so called “agricultural production structures”. The role of agriculture as a social buffer is also observed over the period studied, in addition to other forms of regulation which have emerged (national and international migrations). Structural evolutions arethen analysed using different databases. We observed a decrease in smaller units for the benefit of the average farms. Larger farms have also known a decrease in number and in size, which we attribute to restitution and to the end of privatization. The thesis attempts to identify the factors of these evolutions (survival and growth) using an econometric model in two stages. For that purposewe are also compare the evolution of Romanian structures to those of other European countries including Hungary and Slovenia. Finally, a policy evaluation is conducted on a series of measures identified to have restructuring goal. It appears that in general the absorption of funds, the intermediate target, is prefered to rural penetration of these levers, which is the final objective of thepolicy. Thus, while support for average farms seems relevant somes limitations appear in the implementation. Finally, the reorientation of the agricultural population will not be achieved onlyby the measures studied, for they are under-budgeted or because their effects are over-estimated
