The managing of the project is a systematic approach. However, managing of the complex project is not similar with the managing of conventional projects. In complex project certain amount of the uncertainty is involved. In order to mitigate the effects of the uncertainty involved in the outcome of the complex project the collaboration between the system engineer and the project manager is important. The paper discusses about the significance of the system engineers and the project managers in the development of the project. Apart from that the importance of the collaboration between the system engineers and the project managers has been discussed in this paper.