With the advent of Network-Centric Warfare (NCW) concepts, Command and Control (C2) Systems need efficient methods for communicating between heterogeneous systems. To extract or exchange various levels of information within the networks requires interoperability between human and machine as well as between machine and machine. This dissertation explores the Information Exchange Framework (IEF) concept of distributed data fusion sensor networks in Network-centric environments. It is used to synthesize integrative battlefield pictures by combining the Battle Management Language (BML) and System Entity Structure (SES) ontology framework for C2 systems. The SES is an ontology framework that can facilitate information exchange in a network environment. From the perspective of the SES framework, BML serves to express pragmatic frames, since it can specify the information desired by a consumer in an unambiguous way. This thesis formulates information exchange in the SES ontology via BML and defines novel pruning and transformation processes of the SES to extract and fuse data into higher level representations. This supports the interoperability between human users and other sensor systems. The efficacy of such data fusion and exchange is illustrated with several battlefield scenario examples.A second intercommunication issue between sensor systems is how to ensure efficient and effective message passing. This is studied by using Cursor-on-Target (CoT), an effort to standardize a battlefield data exchange format. CoT regulates only a few essential data types as standard and has a simple and efficient structure to hold a wide range of message formats used in dissimilar military enterprises. This thesis adopts the common message type into radar sensor networks to manage the target tracking problem in distributed sensor networks.To demonstrate the effectiveness of the proposed Information Exchange Framework for data fusion systems, we illustrate the approach in an air defense operation scenario using DEVS modeling and simulation. The examples depict basic air defense operation procedure. The demonstration shows that the information requested by a commander is delivered in the right way at the right time so that it can support agile decision making against threats.