SPSS (The Statistical Package for the Social Sciences) is a computer program which enables data from surveys and experiments to be analyzed fully and flexibly. It has facilities for the extensive manipulation and transformation of data, and includes a wide range of procedures for both simple and highly complex statistical analysis. It also provides the opportu nity for the researcher to produce fully labelled tables and graphs which can be easily incorporated into a final project report. Over the 20 years since it was first devised, the versatile SPSS system has become an indispensable tool for many workers in social science research (including psychology, sociology, politics, human geography, business management, etc.) and in business and government. Many of the largest and most important surveys in the past two decades have been analyzed using one or other version of the system. SPSS is regularly used by government agencies, and by many major industrial corporations, market research companies and opinion poll organizations. For many years SPSS could be run only on large (mainframe) computers of the kind found in the specialist computer installations within universities and large corporations. Advances in the speed, power and memory of microcomputers, however, have recently made it possible to produce a powerful version of SPSS for use on the desk-top machines of the IBM PC (personal computer) family.