Building large science facilities in the framework of national or international collaboration becomes more and more common in the science community, since sharing resources and infrastructure as well as operation cost allows for a better utilization as well as more reliable support during construction and operation. It also brings overhead in managing an increased number of interfaces, be they technical, personnel or even political. The Spallation Neutron Source, a collaboration among six US national laboratories is one more recent example that concluded successfully. The LHC at CERN is another one and ITER or XFEL are other ones that are still in the early construction phase. They all have different management models and some of the advantages and disadvantages are being discussed together with the scientific merits, which after all drive everybody to build them.