IntroductionAs part of the ongoing agrarian transformation in Northeast Thailand (commonly called Isan), major changes of rural households have been occurring. For instance, the average size of households has decreased, and nuclear households, formerly the predominant type, have declined in number, and new household types have been emerging. Associated with changes in household structure are changes in sources of income, which are becoming increasingly diversified, with a decline in the contribution made by agriculture and a growing share of income coming from non-agricultural sources. So marked is this shift that contemporary Isan agricultural households have been called part-time (Takeuchi 2004; Rigg 2005; Grandstaff et al. 2008).Although many of these broad changes in rural households and their sources of income have been discussed by other researchers at a rather general level (Smith 1978; Grandstaff et al. 2008; Rigg and Salamanca 2009; 2011; Keyes 2010; Rigg et al. 2012; Chawanote and Barrett 2013), no detailed descriptions of the nature of changes occurring at the village level have been published. Moreover, many members of the general public, as well as academics, journalists, and policy makers, continue to cling to the old stereotype of rural Isan villagers as poor rainfed rice farmers and have not yet perceived the extent to which rural society and economy in the region have changed. Understanding the reality of rural people's livelihoods in Isan is essential in order to formulate more realistic development policies that will truly serve the interests of local people in the region. Therefore, we undertook this study in a village in Khon Kaen Province in Northeast Thailand in order to describe the current structure of rural households and identify their sources of income. In this paper, we seek to: (1) describe the composition of rural households and classify them into structural types; (2) examine changes that have occurred in the size and types of households over the past 50 years; (3) examine the relationship of household structures and age distribution, types of livelihoods, and agricultural activities; (4) identify the income sources of different types of households; and (5) examine the relationship of household structures with levels of income and debt.Overview of Nong Ben VillageThis research was carried out in Nong Ben village (16°37T2N, 102°49'59E) in Khon Kaen Province. The village is located approximately 20 kilometers northeast of Khon Kaen Municipality along National Highway No. 2 (Fig. 1). Nong Ben village is one of 10 villages in Non Thon Subdistrict (tambol). Nong Ben was a single village (Muban) until 2006, when it was divided into two administrative villages, each with its own headman.The village area of Nong Ben is about 6,291 rai (1,007 ha) (Sunantha 2002). The total agricultural area was about 5,039 rai (806 ha) in 2005 but had declined to around 4,111 rai (658 ha) in 2011. Water for irrigation is supplied by a canal from the Ubolratana dam in Nam Phong District, which is around 30 kilometers from the village. After irrigation first came to the village in 1968, the household economy of the villagers changed dramatically because it became possible to plant a second rice crop in the dry season and to cultivate other valuable crops such as flowers and vegetables.There are three different agricultural land-use in the village: (1) rainfed upland cash crop fields (cassava, sugarcane, and rubber); (2) irrigated fields used to grow rice and other crops (e.g., flowers and vegetables); and (3) rainfed paddy fields. The total area of paddy fields in 2002 was about 3,019 rai (483 ha), which had declined to 2,501 rai (400 ha) in 2011. In 2006, about 53% of village households had only irrigated paddy fields, 11% had only rainfed paddy fields, and 36% had both types of paddy fields (Shirai et al. 2007). The villagers plant glutinous rice (RD6 variety), mostly for self-consumption, and jasmine rice (KDML105 variety) for sale. …