Firstly, the spectrum of diseases are different. Diseases of infection are still quite prevalent in many parts of the developing world. Moreover, a number of diseases occur in developing countries which are only rarely, if ever, seen in the Western world. One can cite the examples of tropical calcific pancreatitis and veno-occlusive disease of liver, among others. Secondly, the paucity of diagnostic and therapeutic modalities makes the clinical approach to a patient somewhat different in developing countries. Thirdly, access to Western textbooks is limited in many areas of the developing world. The contributors have kept these things in mind while preparing their part of the book.