Emerging workloads on supercomputing platforms are pushing the limits of traditional high-performance computing software environments. Multi-physics, coupled simulations, big data processing and machine learning frameworks, and multi-component workloads pose serious challenges to system and application developers. At the heart of the problem is the lack of cross-stack coordination to enable flexible resource management among multiple runtime components. In this work we analyze seven, real-world applications that represent emerging workloads and illustrate the scope and magnitude of the problem. We then extract several themes from these applications that highlight next-generation requirements for node resource managers. Finally, using these requirements, we propose a general, cross-stack coordination framework and outline its components and functionality.