Marine spatial planning (MSP) is heralded as a new approach to sustain economic, ecological, and cultural resources for future generations by identifying areas best suited for various human uses. If MSP is to succeed over the long term, it must be more than lines on maps. It must account for the dynamic nature of ocean ecosystems -- variability over days, years, decades, and longer -- that can interact strongly with climate change. How do we create an MSP framework that reflects the fluidity and complexity of ocean ecosystems without getting bogged down? Under its first-ever National Ocean Policy, the United States is now wrestling with how to design MSP that sustains the delivery of bountiful services from coasts and oceans. This session will present them with the knowledge, tools, and policy options to turn promises into practice. Drawing on expertise from ecology, fisheries, oceanography, economics, and law, this session will highlight cutting-edge knowledge of variability and change in marine ecosystems and the human activities that depend on them. Speakers will explore how marine ecosystems from New England to Baja are changing over time and yet can still be resilient in the face of climate change; describe physical changes in oceans across the globe and the implications of those changes for larval dispersal and ecosystem dynamics; present novel measures to apply ecosystem services to decision-making; and offer innovative policy options to anticipate and adapt to change.