This document discusses cloud lock-in and interoperability. It begins with recapping cloud computing concepts like deployment models and service models. It then defines cloud lock-in and discusses how portability and interoperability can help address lock-in concerns. Emerging standards from groups like DMTF, SNIA, and CSA that aim to improve interoperability are presented. Best practices for vendors and customers to reduce lock-in are outlined. While lock-in exists now due to proprietary systems, the future of interoperability is promising. Standards and informed customer decisions can help minimize negative impacts of lock-in.