Cash fl ow considerations can be critical to project success. Companies can default and run into insolvency due to a lack of profi tability, but also due to insuffi cient liquidity. One may say that it does not matter if a company goes bankrupt, as long as it is not their own, but in a complex project support network (PSN), this may be too shortsighted; one contractor in dire straits may fi nancially damage other contractors, subcontractors, and the customer, as well as jeopardizing the entire project.