The article describes a software package created to measure the return on marketing investment for organizations involved in e-commerce. It is based on web application technology and includes a database system which makes it suitable for use by consultancy companies involved in offering evidence and advice regarding marketing strategies of their customers. A complete solution consisting of the structure for the database, the user friendly interface and the constellation for the network infrastructure is presented. The first tests in a Swedish based company Adonline, showed that it significantly reduces the time necessary for the analysis of return on marketing investment and the effort in creating reports for their customers.