The study of Behavioural finance is relatively new and examines how individuals' attitudes and behaviour affect their financial decisions and financial markets. Behavioural Finance builds on existing knowledge and skills that students have already gained on an introductory finance or corporate finance course. The primary focus of the book is on how behavioural approaches extend what students already know. At each stage the theory is developed by application to the FTSE 100 companies and their valuation and strategy. This approach helps the reader understand how behavioural models can be applied to everyday problems faced by practitioners at both a market and individual company level. The book develops simple formal expositions of existing attempts to model the impact of behavioural bias on investor/managers' decisions. Where possible this is done grounding the discussion in practical, numerical, examples from the financial press and business life.