The purpose of this study is to summarize the various barriers to more widespread distribution of biofuels through our common carrier fuel distribution system, which includes pipelines, barges and rail, fuel tankage, and distribution terminals, and with a special focus on biofuels, which may come into increased usage in the future. Addressing these barriers is necessary to allow the more widespread utilization and distribution of biofuels, in support of a renewable fuels standard and possible future low-carbon fuel standards. By identifying these barriers early, for fuels not currently in widespread use, they can be addressed in related research and development. These barriers can be classified into several categories, including operating practice, regulatory, technical, and acceptability barriers. Possible solutions to these issues are discussed, including compatibility evaluation, changes to biofuels, regulatory changes, and changes in the distribution system or distribution practices. No actual experimental research has been conducted in the writing of this report, but results are used to develop recommendations for future research and additional study as appropriate.