Based on a course by the author at the University of Cambridge, this comprehensive text on turbulence and fluid dynamics is aimed at year 4 undergraduates and graduates in applied mathematics, physics and engineering and provides an ideal reference for industry professionals and researchers. It bridges the gap between elementary accounts of turbulence found in undergraduate texts and more rigorous accounts given in monographs on the subject. Containing exercises and many examples, the author combines the maximum of physical insight with the minimum of mathematical detail where possible. The text is highly illustrated throughout, and includes color plates; all required mathematical techniques are covered in extensive appendices. The text is divided into three parts: Part I consists of a traditional introduction to the classical aspects of turbulence, the nature of turbulence, and the equations of fluid mechanics. Mathematics is kept to a minimum, presupposing only an elementary knowledge of fluid mechanics and statistics. Part II tackles the problem of homogeneous turbulence with a focus on numerical methods. Part III covers certain special topics rarely discussed in introductory texts. Many geophysical and astrophysical flows are dominated by the effects of body forces, such as buoyancy, Coriolis and Lorentz forces. Moreover, certain large-scale flows are approximately two-dimensional and this has led to a concerted investigation of two-dimensional turbulence over the last few years. Both the influence of body forces and two-dimensional turbulence are discussed.