The next wave of industries and AI requires us to build physically accurate virtual worlds indistinguishable from reality. Building virtual worlds is hard, and today's existing universe of 3D assets is inadequate, representing just the visual representation of an object. Whether building digital twins or virtual worlds for training and testing autonomous vehicles or robots, 3D assets require many more technical properties, requiring a need to develop and adopt novel processes, techniques, and tools. NVIDIA is introducing a new class of 3D assets called "SimReady" assets — the building blocks of virtual worlds. SimReady assets are more than just 3D objects — they encompass accurate physical properties, behavior, and connected data streams built on Universal Scene Description (USD). We'll show you how you can get started with SimReady USD assets, and present the tools and techniques required to develop and test these assets.