In the last few years Agile methodologies appeared as a reaction to traditional ways of developing software and acknowledge the need for an alternative to documentation driven, heavyweight software development processes. This paper shortly presents an agile approach for software development of e-business applications. The approach, named eXPERT, is applicable to small teams developing projects characterised by often changing requirements, tight schedules, and high quality demands. The present article describes a case study about eXPERT approach implementation at software developing company. Experiment results based on preliminary defined series of metrics are presented and analyzed.