The disintegration of the haciendas began as a result of the Mexican Revolution, and it ended with the redistribution of their land during the Agrarian Reform. During the 1930s and 1940s, huge rural estates were fragmented and converted into ejidos or minifundios. Ejidos are tracts of land that are granted as communal property to rural towns. They are worked by members of the community, who benefit from the land's yield. Ejidal properties cannot be sold or transferred. The minifundios are small private pieces of property, amounting on the average to 100 hectares but varying according to the region of the country and type of soil. Between 1934 and 1940, approximately 17,900,000 hectares (44,230,900 acres) were redistributed, representing close to half of all tillable land. This repartitioning of the land has continued into the present, though its pace has been much slower.

As hacienda property was broken up, the hacienda owners, the hacendados, were left in possession of the hacienda buildings and the immediate land around them, the size of which was restricted by the limits that were set for these small properties. This meant that immense haciendas were reduced to very tiny ranches. Along with their land, the hacendados lost access to water, they lost their means of irrigation, machinery, and livestock.

Because of these measures, the hacienda system was annihilated. For the majority of the hacendados, the few acres left them turned out to be unproductive land, and their hardships were magnified by the instability and the violence that prevailed in the country. As a result, many hacienda buildings were abandoned or were destined for new purposes.

Only a few of the ex-haciendas remained in production. Some landowners took advantage of the limited property left to them to plant lucrative, high-yielding crops, while others augmented the size of their cultivated land by leasing adjoining land or by purchasing it under assumed names.

When Bartlett began his hacienda visits in the 1940s, he found many of the hacienda buildings in ruins, exposed to the ravages of time and vandalism. Buildings had been converted into chicken coops, pigsties, public apartments, and machine shops. Others served as sources for construction materials, from which were scavenged rocks, bricks, beams, and tiles for the habitations of the local population. In some cases the destruction was total: All the hacienda's structures were removed, and only the name of the place alluded to the fact that an hacienda had ever existed there.

At other haciendas, buildings were adapted to new uses. They were transformed into hotels, resorts, government buildings, barracks, hospitals, restaurants, and schools. The exterior of the buildings were generally left intact; interiors were completely changed.