Every professional firm must satisfy three goals: client service, professional satisfaction of the people and financial success to reward staff and grow.  Therefore, the management of a professional firm requires a delicate balance between the demands of the clients, staff and economic profitability.  Using system dynamics methodology, this study analyses the dynamic problems facing professional services firms and how can be achieved a balanced organisational structure.  The study is based on a modelling project aimed to help the process of staff budgeting of a professional services firm in the financial industry.