This book grew out of the senior level lecture course I teach at Delft Univer sity and which I have taught in recent years at Eindhoven University and the University of Utrecht. Numerous discussions with students and colleagues led me to the conclusion that in spite of the existence of excellent books on the statistical theory of fluids, there is a gap between the fundamental theory and application of its concepts and techniques to practical problems. This book is an attempt to at least partially fill it. It is not intended to be a thorough and comprehensive review of liquid state theory,...