The maritime shipping sector is facing another propulsion revolution. Researchers are slowly converging towards a consensus on the most likely energy carriers and propulsion systems serving ships in 2030 and beyond. International regulators are tightening design requirements for vessels and contemplate a comprehensive strategy to reduce greenhouse gasses on top of measures already in place to reduce emissions that impact air quality. For many governments and citizens progress is not going fast enough however sparking local initiatives. The long-term future is likely to see a wide scope of fuels leading to challenges in energy production, cargo flows, (e-)bunkering infrastructure and safety regimes. Port of Rotterdam has a long-term Energy Transition perspective, and actively supports clean maritime shipping initiatives. Cross-sectoral collaboration in the whole value chain for marine propulsion is crucial to reach our common goals.