Compute, memory, storage, and connectivity demands are forcing the industry to adapt as it meets the expanding needs of cloud, edge, enterprise, 5G, and high-performance computing. UCIe — Universal Chiplet Interconnect Express — is an open industry standard founded by the leaders in semiconductors, packaging, IP suppliers, foundries, and cloud service providers to address customer requests for more customizable package-level integration. The organization is also fostering an open chiplet ecosystem by offering high-bandwidth, low-latency, power-efficient, and cost-effective on-package connectivity between chiplets. The UCIe 1.0 specification provides a fully defined stack that comprehends plug-and-play interoperability of chiplets on a package — similar to the seamless interplay on board with off-package interconnect standards such PCI Express®, Universal Serial Bus (USB)®, and Compute Express Link™ (CXL™). This presentation explores the industry demand that brought about the UCIe specification and shares how end-users can easily mix and match chiplet components provided by a multi-vendor ecosystem for System-on-Chip (SoC) construction, including customized SoC.