When we group the activities into disciplines we mask the interactions among the activities portraying the design process as linear. This is not the case. The process is better described as “quasi-linear” (LAVERGHETTA, 1998). As point Laverghetta, design activities within the spiral rely on input from and provide output to almost every node of the process. As such, engineers and designers must have access to information (whether actual or estimated) from each design discipline and they must be acutely aware of the potential feedback effects caused by the changing output from their own products. To control it, managerial activities play a capital role into the process. However, it is necessary to map the activities interactions of the process.