Mobile computing presents unique challenges due to its inherent constraints. These include resource limitations, mobility-related risks, variable connectivity, and finite energy sources. These factors complicate the design of distributed systems and require rethinking traditional approaches to information access. Adaptation is crucial in mobile computing, balancing autonomy and interdependence. The paper explores adaptation strategies, ranging from application-transparent to application-aware, and discusses the extended client-server model, which allows temporary blurring of client-server roles to enhance performance and availability. The Coda File System demonstrates disconnected operation, optimistic replication, and support for weak connectivity. Odyssey, a platform for mobile computing, explores application-aware adaptation. Key research topics include caching metrics, semantic callbacks and validators, resource revocation, analysis of adaptation, and global estimation from local observations. These areas offer fertile ground for future research, with challenges in developing effective metrics, efficient validation mechanisms, and strategies for resource management and system stability. The paper emphasizes the need for further investigation into these topics to advance mobile computing systems. Mobile computing is a fundamental influence on distributed systems, shaping their evolution in ways that are only beginning to be understood.Mobile computing presents unique challenges due to its inherent constraints. These include resource limitations, mobility-related risks, variable connectivity, and finite energy sources. These factors complicate the design of distributed systems and require rethinking traditional approaches to information access. Adaptation is crucial in mobile computing, balancing autonomy and interdependence. The paper explores adaptation strategies, ranging from application-transparent to application-aware, and discusses the extended client-server model, which allows temporary blurring of client-server roles to enhance performance and availability. The Coda File System demonstrates disconnected operation, optimistic replication, and support for weak connectivity. Odyssey, a platform for mobile computing, explores application-aware adaptation. Key research topics include caching metrics, semantic callbacks and validators, resource revocation, analysis of adaptation, and global estimation from local observations. These areas offer fertile ground for future research, with challenges in developing effective metrics, efficient validation mechanisms, and strategies for resource management and system stability. The paper emphasizes the need for further investigation into these topics to advance mobile computing systems. Mobile computing is a fundamental influence on distributed systems, shaping their evolution in ways that are only beginning to be understood.