Agricultural extension programs or pilots based on the Farmer Field School (FFS) approach are being implemented in many developing countries in Asia and Africa. Evidence from the Philippines and Indonesia, two key areas in implementing this extension effort, shows that fiscal unsustainability of the FFS if applied on a large scale is a risk that cannot be ignored. Because of high costs per trained farmer, the amount of funding for extension in the Philippines cannot provide for significant farmer outreach. Farmer-led field schools are viewed by some as a way out of this fiscal dilemma if part of the cost is shifted to the community, but farm survey data from Indonesia indicate that the extent of the takeover of training responsibilities by farmers has been minor. Furthermore, farmer-led schools are still not funded mainly by community resources. The results suggest a need for great selectivity and caution in initiating FFS pilots, with a focus on the fiscal sustainability of the program if the intention is to scale up these activities.