An "agent" system allows factions to hire freelance persons each with their own specific abilities. Some assist scientific research, others in reconnaissance, resource harvesting and so forth. Each recalls his previous contracts, this affects price. Further, they have an attitude towards their fellow agents, ranging from love to resentment. Research plays a major part in Earth 2160, and factions can choose numerous technologies to research, often at the same time. Research centres are still prevalent, and the number constructed will have an effect on the speed of research. Earth 2160 uses modular construction, in which buildings and units can be constructed from a wide assortment of basic parts. The game economy is based upon three material types: Water, Metal, and Crystals.