The inequitable distribution of land for cultivation in many countries is a major factor in perpetuating a subsistence peasant economy. There are instances where landlords claim from the share-cropper as much as three-fourths of the produce. Similar problems of land tenure exist in tribal communities where neither the member of the tribe as an individual nor his family as a group is entitled to the continuous possession of land. These systems provide few incentives for land conservation and improvement, and result in land deterioration. With the application of agrarian reform laws, new social and economic problems are encountered. The size of the distributed farm in some countries may not make for economic viability. Holdings are generally too small to offer adequate employment opportunities for growing families. Drains and canals, which were previously owned by one landlord who had the resources to maintain them, are now, following reform, owned by a large number of shareholders. Programmes of land distribution often have to be carried out at the price of a decrease in productivity. While bigger land holdings permit the use of extensive techniques such as mechanized farming, smaller holdings may run into difficulties in supporting investments of this nature.
It is estimated that 80% of Latin America's land is owned by less than 10% of its people, or that 50% of the farm land in many parts of Asia is owned by less than 10% of farmers. In the USA since the 1950s, concentration of farm ownership has been encouraged by favouring large landholders, whether through subsidies, non-enforcement of acreage limits on irrigation from federally funded projects, or the imposition of regulations with which small farmers cannot afford to comply. The increasing scale of farms has contributed to a demand for large-scale technologies which tend to be too costly for any but the wealthiest farmers. These tend to displace those suitable to farming on a smaller scale.
In Europe, a total of 800,000 agricultural holdings (10%) disappeared between 1970 and 1987, whilst the size of farms increased, although the rate differed somewhat from Member State to State.