The first chapter represents an introduction to project management and its main elements to be managed. Then, as this project is focused on the costs, there is deep study of the existing cost estimation techniques for project as well as a description of the cost estimation techniques applied to software development. Chapter 2 gives a detailed description about Wireless Sensor Networks, their properties, structure and applications. Once defined, the application of WSN to the agricultural field it is also analyzed in order to show the advantages of using sensor networks in irrigation systems introducing the parameters that this kind of network can control. In the third chapter there is a detailed description of the network design and the choice of its materials. Furthermore, there is an explanation about the process to carry out the developments of the application where the network runs. Finally, in the fourth chapter the chosen techniques to estimate the cost are described. Furthermore, all the costs which have influence in the network are defined and analyzed, concluding the chapter with a budget with the required price to implement the whole project.