Marcia Moraes highlights lessons from Brazil's experience as a biofuel producer (Nature 474, S25; 2011), but some important ones are missing if production is to meet social and environmental standards.

First, treat the workforce consistently, and well. In some regions, sugar-cane workers are well paid, but in others — notably in west-central and northeastern Brazil — they do not have proper contracts and conditions are appalling.

Second, include small-scale farmers, who have been excluded from Brazil's ethanol sector since it started 35 years ago, on the grounds of economic inefficiency. Follow the example of its national programme for biodiesel, which promotes partnerships between the oilseed industry and small farmers and peasants.

Third, follow environmental laws. Sugar-cane farms preserve only 11% of their land as forest (Brazilian Institute of Geography and Statistics Censo Agropecuário 2006 IBGE; 2009), although the Forest Code legislation stipulates that at least 20% should be forested. Even if the Brazilian government revises the law to reduce that percentage, sugar-cane farms will not have sufficient natural reserves to meet the legislation.

Despite much opposition, sugar-cane production has already been prohibited in the Amazon and Pantanal regions, even while deforestation proceeds unabated in the biodiversity hot spots of the Cerrado biome and the mesophytic Atlantic rainforest.