In this model, a company works as a paid consultant, with contracts granted on the basis of the higher level of knowledge of their employees. Any company can implement this model, as there are no limitations that prevent a competent technician from gaining an arbitrarily deep experience of open source software systems. Of course, this also means that any firm using this model is exposed to the risk of being superseded by someone else, if the level of competence is reached but not maintained. An example of this model is LinuxCare, a firm specializing in consulting on GNU/Linux systems, which also sells support.