The aim of this paper is to analyse the development of ways to identify troublesome service situations. It is assumed that difficulties arise from a lack of consistency between the new market orientation of services, and the clerks? understanding of public service itself. Clerks have to manage the commercial, contractual and relational aspects of services, as well as adapt the prescribed task regulations to the diversity of customers? needs and expectations.
An ergonomic analysis of clerks? activities reveals that certain situations give rise to goal conflict, which clerks then have to solve. The results also show variations in dealing with conflicts according to the age and professional experience of the employee.
By interpreting the results of the study within the framework of Piaget?s theory of equilibrium, it seems that clerks aspire to achieving a happy medium between the system requirements (hierarchy, rules and tools); customers? demands, team and colleagues? characteristics and behaviour; and their own needs. Changes in the balance of these requirements are related to age and experience. They are mainly characterised by: the extension and co-ordination of the different areas dealt with during the same transaction where clerks use ' multi-functional strategies '?; the lengthening of the temporal span of activity; and the modification of rules and procedures.
From a cognitive point of view, these changes are interpreted as being characteristic of the development of clerks? skills.
From a sociological point of view, it can be concluded that clerks become more autonomous and take greater latitude. This development is interlaced with group dynamics, which differ from one office to another.