Recent challenges for sustainable development are linked to large-scale land use transition and its impact on forest-dependent populations. Alternatively, agroforestry practices offer multiple opportunities to farmers to improve farm production and incomes; they also result in productive and protective forests functions. Large cardamom (Amomum subulatum) cultivation with N2-fixing Himalayan alder (Alnus nepalensis) as a shade tree in the Eastern Himalayas is one such alternative agroforestry practice. Performances were analyzed for cardamom agroforestry with N2-fixing alder (alder-cardamom), without alder (forest-cardamom), and with an age series of alder-cardamom between 5 to 40 years. Alder tree association accelerates the cycling of both nitrogen and phosphorus, and more than doubles production and yield. While increasing soil fertility, alder-cardamom agroforestry also conserves soil and water, and sequesters atmospheric carbon. This leads to ecological sustainability in mountain watersheds. It also provides a high aesthetic value and draws upon cultural, recreational and educational values that are harnessed by local communities as non-farming employment opportunities in ecotourism. Ecosystem services provided by cardamom agroforestry contribute to the well being of the upland people and at the same time profit the beneficiaries downstream.