Recent developments in information and communication technologies and their incor- poration into the medical domain have opened doors for the enhancement of health care services and thereby increasing the work ow at a reasonable rate. However, to implement such services, current medical system needs to be exible enough to support integration with other systems. This integration should be achieved in a secure manner and the resultant service should be made available to all health professionals and patients. This thesis proposes a new infrastructure for secure medical image sharing between legacy PACS and DI-r. The solution employs OpenID standard for user authentication, OAuth service to grant authorization and IHE XDS-I pro les to store and retrieve medical im- ages and associated meta data. In the proposed infrastructure cooperative agents are employed to provide a user action, patient consent and system policy based access con- trol mechanism to securely share medical images. This allows safe integration of PACS and DI-r systems within a standard EHR system. In addition to this, a behavior-pattern based security policy enhancement feature is added to the system to assist the system security administrator. The resulting secure and interoperable medical imaging systems are easy to expand and maintain. Behavior of the entire system is analysed using general- purpose model driven development tool IBM Rational Rhapsody. The code generation and animation capability of the tool makes it powerful for running e ective simulations. We mainly explore the use of state charts and their interactions with MySQL database to learn the behavior of the system.