Economists seek to analyze the forces determining prices — not only the prices of goods and services but the prices of the resources used to produce them.  This involves the discovery of two key elements: what governs the way in which human labour, machines, and land are combined in production and how buyers and sellers are brought together in a functioning market.  Because prices of the various things must be interrelated, economists therefore ask how such a “price system” or “market mechanism” hangs together and what conditions are necessary for its survival.

These questions are representative of microeconomics, the part of economics that deals with the behaviour of individual entities such as consumers, business firms, traders, and farmers.  The other major branch of economics is macroeconomics, which focuses attention on aggregates such as the level of income in the whole economy, the volume of total employment, the flow of total investment, and so forth.  Here economists are concerned with the forces determining the income of a country or the level of total investment, and they seek to learn why full employment is so rarely attained and what public policies might help a country achieve higher employment or greater price stability.

But these examples still do not exhaust the range of problems that economists consider.  There is also the important field of development economics, which examines the attitudes and institutions supporting the process of economic development in poor countries as well as those capable of self-sustained economic growth.  In this field the economist is concerned with the extent to which the factors affecting economic development can be manipulated by public policy.