As industry has become more specialized, purchasing has developed into a vital strategic resource. This study identifies the major issues involved and provides critical analysis, overturning many theories and assumptions surrounding purchasing. Through an analysis of buyer behaviour, all the key processes are examined in detail. They include: supplier relations; supplier networks; organization of purchasing; and communication. Five case studies illustrate how these techniques work in practice. This view of purchasing should be of interest to students of consumer behaviour, marketing and organizational studies.