There is growing awareness that ongoing efforts to reduce CO2 emissions will be insufficient to limit global warming to below 2℃ above pre-industrial levels. To meet this target, Carbon Dioxide Removal (CDR) on the order of 10 – 20 Gt CO2/year will be required before the end of the century. While most current CDR technologies applied at scale focus on terrestrial approaches, marine CDR (mCDR) includes methods with some of the largest removal potentials. Actual mCDR field deployments remain limited in scale and operational requirements are still being explored so further research is needed before mCDR can be considered for deployment at scale. This session will focus on the various mCDR technologies, their potential for large-scale deployment and safety considerations, as well as Monitoring, Reporting, and Verification (MRV) required to support them. We welcome contributions from laboratory and mesocosm experiments, small- and large-scale field trials, numerical modelling, and machine-learning approaches to data, with a particular interest in multidisciplinary submissions.