How do you structure a TW2002 type world? Consider a system where the stations aren't warehouses buying and selling commodities that just sort of magically appear in them, but rather trading spaces in a commodities market. So you actually do your trading against other players and computer AIs in a MULE-style auction house: SELL _ _ _ _ _ _ _ _ _ _ _ House 500 _ _ _ _A_ _ _ _ _ _ _ Zerd 370 ___X___________F_____ Huk/Zump 300 (4..) _ _ _ _ _L_ _ _ _ _ Krink 250 _ _ _ _ _ _ _ _ _ _ House 100 BUY In the above, the station warehouse has standing BID/ASK orders to buy as much as possible at 100 and sell as much as possible at 500. Presumably the station owner may dip into this warehouse and manually trade from this commodity pile/cash reserve elsewhere. Zerd (the A) may be a live player, or a computer AI, or an offline player with a standing order to sell some amount at 370 each. Huk and Zump (X and L) are trading at 300, and have exchanged four units so far. Krink is live/ai/offline attempting to buy at 250. walking up or down changes your price, and when a buy line meets a sell line trading happens. I assume that to switch between buy/sell you'd just walk all the way off and around, or exit and come back in with a different status. In addition to trading commodities (or, in fact, any in-game item. Got too many fighters on your hands? transwarp engines? ships?) the game should support contracts. I was originally thinking like a futures market, where you enter an auction that trades in something like " at this warehouse in 24 hours" or some other time frame. Then you meet on a line to agree on price and amount, and the money is delivered instantly for goods delivered later (or, in reverse, as a purchase of goods on credit). An unfulfilled contract past the deadline authorizes the holder to pillage the deadbeat until salvage has compensated for at least as much as the contract was worth in cash (but most likely more). These late contracts may be sold as a commodity themselves, for enterprising bounty hunters to collect on or for traders to flip in more agressive parts of the galaxy. A more generic sort of contract may be nice, so that you just come up with conditions for consideration for both parties, measurements of fulfillment, and consequences for breaking. I was thinking also that planets do all the production of raw materials, but landing is hard on the engines (takes lots of fuel ore, or whatever) and you pay customs for bringing goods to a planet. I'd say all stations are in orbit around a planet of some type (even an inhospitible fuel ore asteroid) and part of the early trading work people do is shuttling from the planet surface to the station. This is also what lots of the alien AIs do. Demand for resources is driven by station upgrades and planetary needs (that fuel ore asteroid doesn't grow its own crops!). Manufacturing facilities may be cheaper on a station, but labor is cheaper on a planet. Need ship upgrades? Those have to be manufactured from raw resources on a station somewhere, and that station has to use resources to build the factory. AIs have a few basic attributes like 'rationality' and 'ethics' (so they can make wild gambles or try to cheat you on a futures contract, or be quiet little ethical investors), and events they observe adjust the bid/ask values they consider acceptable based on these characteristics.