Plasmas are ionized gases, composed of free electrons and positively charged atomic nuclei, whose collective behaviour is strongly influenced by the presence of magnetic fields. Plasmas make up more than 99% of the matter in the Universe. Familiar examples are stars, flames, lightning, and auroras borealis. One practical plasma application is the search for controlled thermonuclear fusion to be used as a new and virtually inexhaustible energy source. Magnetic reconnection is a process whereby the plasma changes its spatial configuration by relaxing the magnetic field that confines it. Relaxation often occurs spontaneously and in explosive ways. A notable example is solar flares, which release streams of charged particles in Space, causing electro-magnetic storms and black out of satellite communications in the Earth magnetosphere. The physics of magnetic reconnection shares many common aspects with phenomena in ordinary fluids, such as vortex cell formation and merging and the path to turbulent behavior. An Introduction to magnetic Reconnection in Plasmas provides an introduction to the theory of magnetic reconnection while emphasizing basic mathematical tools and concepts. It is addressed to senior undergraduate and graduate students, with starred sections for the advanced reader. Plasma specialists who are not already acquainted with the mathematical formalism of magnetic reconnection as well as scientists who have an interest in Astrophysics, Fluid-Dynamics and Nonlinear Physics will also find the book valuable and informative. Reading the book will enable both students and specialists to tackle the vast body of scientific literature on the subject. Provides in-depth coverage of plasma physics and magnetic reconnection Includes starred sections for the advanced reader, and exercises for students Clear and pedagogical writing style with many helpful bibliographical references Mathematics of magnetic reconnection clearly explained