Collaborative design is a major industrial issue, where people from different expertise fields strongly need to cooperate. New Internet Collaboration Tools (ICT) possibilities now allow design processes to be hold over distributed teams. Our goal is to define a collaborative environment based on Internet technologies: Techniques, methods, and tools for CSCW in design. From the design experiment of an electromechanical plunger hold over Internet and involving mechanical and electrical engineers, this paper looks at their collaborative design activity. This leads us to present now communication tools, dedicated to specific tasks that are actually not supported, especially shared concept formalization among technical experts.