This book is dedicated to the development of a methodology for performing the diagnosis of voltage disturbances in electrical power distribution systems, using artificial immune systems (EIS). This is the proposition of a new paradigm in the EIS environment that confers continuous learning (plasticity). This conception allows the composition of a diagnostic system capable of learning continuously, contemplating new types of disturbances arising from the constant evolution of the electrical sector, without the need to restart the learning process. In this context, two artificial immunological algorithms are used. The main application of this new method is to assist the system operation during disturbances, as well as to supervise the protection system, and to be able to follow the evolution of electrical systems acquiring knowledge continuously. To evaluate the effectiveness and performance of this new method, simulations of voltage disturbances in electrical power distribution systems with 5, 33, 84 and 134 bars were carried out in the ATP/EMTP software. This book was produced by professors Simone Silva Frutuoso de Souza and Fernando Parra dos Anjos Lima.