Our paper looks at how price volatility in the Brazilian ethanol industry changes over time and across markets. Demand and supply forces in the energy and food markets are likely to ensure that crude oil, ethanol and feedstock prices co-move in the long-run. Hence, when assessing price volatility changes and spillovers in the ethanol industry, one should also pay attention to the notion of cointegration. Until recently, the methods proposed to estimate cointegration relationships, have not explicitly considered time varying volatility in the data. Seo (2007) suggests an estimator of the cointegration vector that explicitly models conditional heteroskedasticity. More specifically, he proposes a maximum likelihood estimator that estimates the error correction model and the multivariate GARCH process jointly. We follow this proposal.World ethanol production is dominated by the US and Brazil. In 2006 worldwide production totaled 13,489 million gallons, with the US and Brazil producing, respectively, a 36 and a 33% of this quantity. Although both countries produce a conspicuous part of worldwide ethanol, their industries are not equally developed: while the Brazilian market is starting to