Maize is the principle food staple in Zambia, providing both food and income for most of the rural populace. It is estimated that over 50% of the daily caloric intake is derived from maize;with an average consumption of over 85kg per year. Because of the importance of maize, a number of improved maize varieties and sustainable crop management practices have been developed to increase its productivity. Despite these improved agricultural technologies being available for some time now, few studies have analyzed the adoption impacts of these technologies on the economic well-being of smallholder farmers in Zambia. To fill this gap in the literature, this thesis assesses the adoption and impacts of improved maize varieties and sustainable agricultural practices (SAPs) on the welfare of smallholder farmers in the Eastern province of Zambia. To accomplish this objective, we use a number of novel econometric approaches and a comprehensive household survey data from a sample of 810 rural households and 3788 plots. First, the findings suggest that the adoption of improved maize varieties is determined by a whole range of factors that include land cultivated, education of the household head and the total asset holdings of the household. Second, the results show that the adoption of improved maize varieties is associated with higher levels of income, food security, child nutritional status and lower levels of poverty. Third, the counterfactual analysis applied in this thesis shows that if non-adopters had adopted improved maize varieties, they would have realized higher levels of welfare than they currently have. Fourth, the results show that adoption of improved maize alone has greater impacts on maize yields, but given the high cost of inorganic fertilizer that limits the profitability of adoption of improved maize, higher household incomes are associated rather with the adoption of multiple SAPs.