Security is an important barrier to wide adoption of distributed systems for sensitive data storage and management. In particular, one unsolved problem is to ensure that customers data protection policies are honored, regardless of where the data is physically stored and how often it is accessed, modified, and duplicated. This issue calls for two requirements to be satisfied. First, data should be managed in accordance to both owners' preferences and to the local regulations that may apply. Second, although multiple copies may exist, a consistent view across copies should be maintained. Toward addressing these issues, in this work we propose innovative policy enforcement techniques for adaptive sharing of users' outsourced data. We introduce the notion of autonomous self-controlling objects (SCO), that by means of object-oriented programming techniques, encapsulate sensitive resources and assure their protection by means of adaptive security policies of various granularity, and synchronization protocols. Through extensive evaluation, we show that our approach is effective and efficiently manages multiple data copies.