We present a software system to create and implement internal markets in organizations that want to limit the CO2 emissions or the use of scarce resources by their employees. This system can be applied to domains such as business travel by distributing a limited number of permits for business travel-related CO2 emissions at the beginning of a period and then allowing the permits to be traded inside the organization. The system calculates the CO2 emissions caused by planned trips and provides the market mechanisms to trade the permits. The approach can be generalized from emission permits to any scarce good that is assigned by the management to units or individual members of the organization, such as parking spaces. Both cases are described by way of detailed examples.