Real-time permanent monitoring and control is essential to maximize production from oil and gas wells. An interdisciplinary approach is needed for any cost-effective solution that can perform and be sustained in the harsh downhole environment. For open hole horizontal wells, providing power and data through an umbilical is very challenging. Wireless communication is the essential component of any downhole monitoring and control solution in this situation. A wireless solution can also significantly reduce the complexity and cost associated with the wired solutions. In this paper various wireless communication techniques are classified and an extensive review of state-of-the-art downhole applications is presented. Advantages and limitations of each technique are discussed and recommendations are made of possible solutions.