Low-productivity, subsistence-smallholder agriculture everywhere faces tremendous new challenges, in addition to decades-old constraints. Smallholders are threatened by being bypassed by the rise and dominance of domestic and global value chains (DVCs, GVCs). They are also being threatened by global warming, which is already rewriting the basic parameters of temperature and precipitation on which their entire activities depend. These global forces are much too powerful for any farming or livestock enterprise, no matter how rich, to adjust to and thrive without assistance. For subsistence smallholders adjustment is particularly hard.