The thesis consists of three essays on agriculture and poverty in Vietnam. In the first chapter of the dissertation, I employ a comprehensive panel dataset of rural households in Vietnam to investigate the inverse relationship between farm size and total factor productivity. The results underscore a compelling trend: smaller farms consistently demonstrate higher levels of productivity when compared to their larger counterparts. Notably, the analysis demonstrates that land quality does not contribute to explaining total factor productivity. Leveraging stochastic frontier production analysis, the study reveals a discernible inverse negative association between farm size and frontier productivity, concurrently revealing a positive correlation between farm size and technical inefficiency. These empirical findings yield valuable insights into the multifaceted determinants shaping agricultural productivity within the context of rural Vietnam.The second chapter contributes to the literature on the land rights. It investigates the causal effect of land tenure security on agricultural productivity. Vietnam passed a new Land Law in 2013 that extended usufruct rights from 20 to 50 years for households that produce annual crops, while leaving the 50-year period for households that produce perennial crops unchanged. In this paper, we study the impact of this change in tenure security on land productivity and total factor productivity (TFP) at the household level. A difference-in-differences approach with household and district-year fixed effects is implemented to estimate the Land Law’s effect. Empirical findings show that an increase in the duration of land tenure has no statistically significant effect on average land productivity or total factor productivity—a null result. We also find no effect on investment in terms of the likelihood, total number of days or cash that households spend on irrigation, soil, and water conservation. Heterogeneity is explored in a number of dimensions and is found by farm size in the case of land productivity, not TFP. The null findings are explained, in part, by the counterintuitive finding that greater tenure security led households producing annual crops to shift away from agricultural activities and increase the share of income coming from off-farm wages and salaries. While the null findings could be problematic in terms of agricultural production, a shift towards off-farm activities is likely beneficial for family income and poverty reduction. The third chapter focuses on the impact of non-agricultural employment on households’ income. While previous literature has examined the relationship between non-agricultural employment and household welfare, the focus has largely been on correlation rather than causation. In this paper, I utilize an instrumental variable model with a Bartik shift-share instrument to explore the impact of non-agricultural employment on household income. The results in the instrumental variable model with household and year fixed effect show that an additional period of engagement in non-agricultural activities leads to a 10.9% increase in household income. I also employ two-way fixed effects to estimate the relationship between non-agricultural employment and household income. The findings in the model with household and year fixed effect are consistent with Bartik instrumental variable model, although the magnitude is slightly smaller. Furthermore, I examine the heterogeneous effects using interaction analysis. The findings indicate that poor and agricultural households benefit the most from non-agricultural activities.