This document provides an overview of organizational communication. It defines communication and describes effective communication and the communication process. It discusses three common theories of communication - electronic, social, and rhetorical. It also outlines different types of communication like downward, upward, horizontal, interpersonal, and computer-aided. The document then focuses on organizational communication and describes formal small group networks, the grapevine, and barriers to communication like filtering, selective perception, and cultural differences. It provides guidelines for overcoming barriers and discusses gender, cultural and politically correct communication.