Climate-related land use policies in Brazil aimed to reduce greenhouse gas emissions from agriculture. While forest law enforcement helped combat illegal deforestation, positive incentives for farmers were less effective. Market-based incentives like the Low-Carbon Agriculture Plan were hard to verify with current monitoring methods. Farmers' responses to policies were mainly based on costs and benefits, not environmental goals. In Mato Grosso, soybean-cotton and soybean-maize systems dominate. Simulation results show smaller farmer responses to integrated systems and varied carbon balances depending on livestock systems. Lessons from Brazil can guide other countries using economic incentives for climate mitigation in agriculture.