In recent years, the research in laser additive manufacturing (AM) is shifting the focus from rapid prototyping to part fabrication by enabling advanced materials like metals, ceramics, and composites. Here, we focus on the ability of laser metal deposition machines to concurrently feed two and more different materials in a form of fine powder that enables whole new classes of structural and functional materials such as multi-materials, functionally graded materials, nanoparticle-reinforced metal matrix composites, etc. However, the complexity of simultaneous process-material design and optimization requires advanced in situ characterization techniques to be combined with meso-, micro-, and even nanoscale multi-physics modeling to capture all the relevant phenomena (see, for example, Figure 1). In this talk, we will cover recent progress made in the Laboratory for Advanced Materials Processing at Empa towards the design of the next generation of mesoscale multi-physics process models guided by large-scale atomistic simulations and benchmark experiments.