This paper aims to synthesise maritime specialists' perceptions of changing patterns of maritime oil freight flows to 2050. Debate spans published maritime oil flows globally, diverse drivers of future flows including economic growth, shipping market changes and haul lengths. A classic Delphi study to explore the perceptions of likely trends and flows to 2050 recruited a panel of early career and established maritime specialists, many with long term career commitments to this industry. Underpinned by market volatility and legislative uncertainty, the perceptions of both groups coincided and were conservative. Local sourcing, new Arctic seaways and fossil fuel intolerance will tend to reduce oil freight work but perceptions of ship re-routing to avoid for example Emission Control Areas and piracy would tend to lengthen hauls. In advanced industrial nations, reducing energy intensities and diminishing social tolerance of fossil fuels imply gradually reducing maritime oil shipments. However, to achieve radical national commitments to carbon emissions reductions will necessitate specialist education for naturally conservative maritime professionals and vigorous oil import reduction policies to curtail domestic demand for oil shipments