Over the last 20 years there has been a growth in the relative importance of personnel economics as an area of economics. However, due to a lack of suitable data most of the work in this area has been largely theoretical. It is only in the past decade that there has been a growth in the availability of firm-based data sets, making it possible for researchers to begin to test some of these ideas empirically. This thesis analyses data from a rich source of monthly personnel and payroll records from a large banking sector firm. The data is confined to the organisation's U. K operations and is available over the period January 1989 to March 1997 (giving 99 monthly observations). Although personnel data of this this sort is available for the US (see, for example, Baker, Gibbs and Holmstrom (1994) and Lazear (1999)), this is one of the first data sets of its kind to be available for the U. K. This thesis focues on three areas of personnel economics. It analyses the issues of promotion, absenteeism, and labour turnover, paying particular attention in all three cases to gender differences.