Tree-crop commodities (coffee, cocoa, oil palm, rubber and tea) are major sources of income for more than 30 million smallholder farmers but are vulnerable to fluctuating prices and poor market access, climate change, declining productivity of already established plantations due to soil fertility decline and pest and disease build up (cocoa and coffee). They are also the object of controversies around environmental impact of expansion (often into remaining forest areas).

Diversification of production systems is a key strategy to buffer and adapt to climate change (companion trees buffer temperatures, diversifying production, confer ecological and market resilience), raise and stabilize farm income, rejuvenate old plantations and contribute to food and nutrition security (often of migrant farmers).

The priority addresses the following research questions:

• How can tree crops help to build critical livelihood assets?
• What are the best integrated cropping and mixed system options for different situations?
• How can we efficiently, effectively and equitably co-develop design principles for matching, from the options that improve the use of trees by smallholders to the fine scale variation in context
• How can smallholder tree-crop commodity production systems be sustainably managed in the face of climate change, price volatility, declining yield and soil fertility following forest conversion, coupled with constraints on opening new forest areas, and those imposed by the dynamics of migration?
• What is required in terms of an enabling environment to switch from unsustainable monocultures to more diverse and resilient production practices.