Comersus is a sophisticated e-commerce system resulting from research and experience accumulated through years of work in electronic commerce strategies. The system's base was developed in the year 1997 in response to a great multinational firm's requirements. The company wanted to replace its e-commerce system, which was based on a famous product developed in Perl and was considered to be complex, rigid, and expensive. Comersus was successfully installed in that site and in others due to numerous recommendations. Finally, the commercial launching of the solution was decided. The commercial implementation of the system was accomplished in the year 2000, in the Open Source mode. Comersus has been installed all over the world in more than 20.000 sites, and has been renowned in an e-commerce development environment as an economical, flexible, sound, and powerful solution. Comersus solutions provide optimum performance in a variety of industries, including: Software, Book Stores, Retail, High-Tech, Automotive, Consumer Goods, Medical and Services.