This document discusses cloud lock-in and interoperability. It begins with recapping cloud computing concepts like deployment models and service models. It then defines lock-in, portability, and interoperability. Lock-in occurs when there are significant costs to switch cloud vendors. The document discusses how portability and interoperability benefit customers by increasing choice and lowering costs. It provides examples of lock-in for different cloud platforms and analyzes emerging standards from groups like DMTF, SNIA, and CSA. Best practices are outlined to minimize lock-in for IaaS, PaaS and SaaS. The document concludes that while lock-in exists now, interoperability is improving and portability