The economy in "Pax" was based on the mining of five commodities, and the taxation of the population. Taxation only occurred on territories that were not colonies; the conversion from colony to taxable "home planet" occurred when the user built a spaceship port in the territory. Each type of infrastructure required a minimum population to be operated - ports required 2,500 people for instance. Adding infrastructure thus increased the maximum population in the territory, and the tax base. The "city" infrastructure was used solely to build up the population, adding 5,000 people to the maximum.