This set of lecture notes on quantum mechanics aims to teach, in a simple and straightforward manner, the basic theory behind the subject, drawing on examples from all fields of physics to provide both background as well as context.The self-contained book includes a review of classical mechanics and some of the necessary mathematics. Both the standard fare of quantum mechanics texts -- the harmonic oscillator, the hydrogen atom, angular momentum as well as topics such as symmetry with a discussion on periodic potentials, the relativistic electron, spin and scattering theory are covered. Approximation methods are discussed with a view to applications; these include stationary perturbation theory, the WKB approximation, time dependent perturbations and the variational principle. Together, the seventeen chapters provide a very comprehensive introduction to quantum mechanics. Selected problems are collected at the end of each chapter in addition to the numerous exercises sprinkled throughout the text.The book is written in a simple and elegant style, and is characterized by clarity, depth and excellent pedagogical organization.