A wireless sensor network is deployed either inside the phenomenon or very close to it. Unlike some existing sensing techniques, the position of sensor network nodes need not be engineered or predetermined. This allows random deployment in inaccessible terrains. On the other hand, this also means that sensor network protocols and algorithms must possess self-organizing capabilities. Another unique feature of sensor networks is the cooperative effort of sensor nodes. Sensor network nodes are fitted with an onboard processor. Instead of sending the raw data to the nodes responsible for the fusion, sensor network nodes use their processing abilities to locally carry out simple computations and transmit only the required and partially processed data. Realization of sensor networks requires wireless ad hoc networking techniques. In this chapter, we present a survey of protocols and algorithms proposed thus far for wireless sensor networks. Our aim is to provide a better understanding of the current research issues in this field. We also attempt an investigation into understanding design constraints and outline the use of certain tools to meet the design objectives.