Nucleus-outgrower schemes (NOSs) are supposed to be a particularly effective private-sector  mechanism to support smallholder farmers and contribute towards mitigating the problematic  aspects of pure large-scale agricultural investments. This discussion paper uses panel  household survey data collected in two rounds in Zambia to analyse some agro-ecological and  socio-economic impacts of the outgrower programme of one of the largest agricultural  investments in Zambia: Amatheon Agri Zambia (AAZ) Limited. The descriptive results show that  the type of participation in the programme varies across participants and components, with most  participating in trainings. Econometric results suggest the following key findings. First, although  the overall impact of the AAZ outgrower programme on the uptake of conservation agriculture  practices is robust and promising, impacts on the adoption of other agricultural technologies is  less obvious and the effect depends on the type of support provided. Second, the programme  has had a significant impact on maize productivity promoted in the initial phase but not on the  other crops – mainly oilseeds – promoted later. Third, the initially less productive farmers seem  to benefit slightly more than already better performing ones. Fourth, although the impact on  overall household security was insignificant, there is some suggestive evidence (although the  effect is weak) that the programme has a positive effect on improving women’s uptake of  micronutrients. Finally, our findings show that the three components of the programme  (trainings, seed loans and output purchases) have different effects on the adoption of  sustainable agricultural practices and productivity, and to some extent on food security. Overall,  the results suggest that NOSs, with all their risks, can play a role in the adoption of sustainable  agricultural practices, improving farm-level agricultural technologies, providing input credit, and  thereby improving productivity and smallholder livelihoods. However, this is not automatically  the case, as it crucially depends on the design and management of the project; the availability  of good policies and institutions governing the rules of operation; the types of crops promoted;  the duration of the project; and the political commitment of host countries, among others.