This text is concerned with those aspects of mathematics that are necessary for first-degree students of chemistry. It is written from the point of view that an element of mathematical rigour is essential for a proper appreciation of the scope and limitations of mathematical methods, and that the connection between physical principles and their mathematical formulation requires at least as much study as the mathematical principles themselves. It is written with chemistry students particularly in mind because that subject provides a point of view that differs in some respects from that of students of other scientific disciplines. Chemists in particular need insight into three­ dimensional geometry and an appreciation of problems involving many variables. It is also a subject that draws particular benefit from having available two rigorous disciplines, those of mathematics and of thermodynamics. The benefit of rigour is that it provides a degree of certainty which is valuable in a subject of such complexity as is provided by the behaviour of real chemical systems. As an experimen­ tal science, we attempt in chemistry to understand and to predict behaviour by combining precise experimental measurement with such rigorous theory as may be at the time available; these seldom provide a complete picture but do enable areas of uncertainty to be identified.