The risk of biofuel feedstock species becoming invasive, outcompeting native species and threatening livelihoods is increasing as more advanced crops are planted. However, such risk has so far received limited attention. Biofuel crops are not, by definition, invasive. However, they can become invasive, depending on the area where they are cultivated and how the crop is grown. Some plants do have a higher risk of causing a biological invasion if not managed with this in mind. The most important step is prevention. Extra precautions should be taken to minimise the risk. This paper presents guidelines developed by IUCN on biofuels and invasives for decision makers and biofuel producers to minimise risks of biological invasions along the biofuels supply chain, from planning, importation, production to transportation and processing. Overall, it is recommended to follow a precautionary approach, comply with relevant regulations and extend assessment and monitoring beyond the field. (C) 2012 Elsevier Ltd. All rights reserved.