Economic principles, combined with the findings of agricultural technologists, form the basis ofthe field of study called ‘farm management'. From this blend has come tools and techniques for analysing different courses of action and for making decisions. Underlying ways of applying these decision-making aids is the idea of getting a bit more from limited resources.

In this text we have aimed our message at those who directly affect the lives of small farmers in the tropics. This target group includes farm extension and advisory officers, students and teachers of agriculture at colleges and universities, bureaucrats and administrators, employees of the suppliers of credit (and other farm inputs) and managers and staff of parastatals and state farms. Most of these people can use the principles and techniques offarm management economics to help families running either semi-subsistence or commercial farms in the tropics to get more from the limited resources with which they have to work. If the lot of farmers and their families can be improved, it is likely that their society will also benefit.

In Chapter I Introduction, we try to show the potential contribution of applied farm management economics to fulfilling some of the more important basic human ‘wants', and to highlight the pivotal role, and some of the practical problems, of the extension worker in helping his farmer-clients.

In Chapter 2, Farm management, we have tried to explain our concept of farm management as it applies to both semi-subsistence and semi-commercial farms. Rather than listing a number of general platitudes about ‘management', as is common in many management texts, we have been both specific and prescriptive, setting the scene for detailed explanations in later sections.

Chapter 3, Farm analysis and planning, contains a checklist of the main human, physical and financial factors which influence the way in which a farm operates. Each broad category is discussed under three headings: the present situation, potential, and limitations or restraints on achieving the potential.

In Principles of production, Chapter 4, the problem of deciding on the number of weedings a crop should be given to make most profit is used as a simple example to demonstrate some principles which apply to most. production situations. This involves explaining some basic economic concepts. These concepts are at the heart of farm management analysis and planning and are used often in the rest of the book.