Introduction: Many newer players are unaware of the sheer power of Espionage. They ignore it except for putting up Courthouses and complaining about pillaged resources. I use Espionage in almost all my games, sometimes stealing techs from Construction to Computers. In this guide, I hope to help new players get in the habit of involving Espionage in their games. This is not a guide intended to focus on the minutiae Espionage Mechanics. Many people have already done that better than I could. Instead, I will focus on what we can do with those mechanics. Espionage Scales with Horizontal Growth: What's one thing you notice about the Espionage buildings? They all generate Raw EP (except Castles, but those suck anyways). In contrast, you cannot generate Raw Beakers except by Sankore, or Raw Commerce except by Trade Routes/Harbor/Customs House. Basically, you can build EP via city buildings, you can't do the same with anything else. Now think about this: If you have 6 cities with Courthouse/Jail/Sec Bureau/Intel Agency, you wouldn't be generating very much EP. Sure, you could Cottage-spam them and put all your points into the EP slider, but why bother? Cottaged cities don't have too many hammers, and you're better off using them on Library/University/Academy/Observatories and direct research. But what if, instead of 6 cities, you had 16? And a lot of these cities had more hammers, making it easier to build the Espionage buildings? Suddenly, it becomes a lot more attractive to spam Espionage buildings, especially since a lot of these cities won't be commerce superstars. In fact, in this case Espionage is pretty much your best option provided you have a buddy to steal from. This is when you will be using Espionage-based economies: when you have a lot of cities and hammers. If you have a smaller empire, stick to direct research. Regarding Cottages Cottages become very strong late in the game. If you have a lot of land and a lot of Cottages, why should you bother with Espionage? You're probably in a position to win already, and you're just wasting your time. Most players who will be using Espionage are "SE" (this is an archaic term, most people don't use it anymore ) players who used excess food or wonders to generate Great People earlier in the game, which gave them an advantage. The SE players leveraged a temporary tech lead to give them a "Breakout", where they rapidly expanded their empire through war, usually in the Renaissance. But now it's the Industrial Age, people are getting lovely techs like Communism/Biology/Railroad, and the "SE" players are experiencing one of 2 fates. 1) You've expanded onto so much profitable land that you're still up there in tech, and by the end of the game you're pulling around 3000 bpt with micro. Usually this happens when you've thoroughly ravaged some poor backwards AIs and got good land from them. I'm sure everyone has had these games at some point. 2) The RNG screwed your start position, you got bad trade partners, you got bogged down in a war, or you just played badly. You were doing fine early, but now your bpt isn't good enough to match that ridiculously bonused Pacal whose Cottages have matured into FEUSS-powered Towns. The second case is when you will need Espionage to pull off a Conq/Dom or Space win. Transitioning into Espionage: If you have Stone or IND, or have a lot of open land, or are next to a tech fiend, you should consider building the Great Wall. Aside from saving money on fogbusters, the Great Spy points can pay off when they net you an early Great Spy. You should settle him in the Capital, because he also gives you a bit of research. Otherwise, you don't really need to worry about Espionage early on besides building Courthouses and running a Spy specialist here and there. Just remember to allocate your EP's towards your chosen target, and you might be able to occasionally steal a tech. So let's fast forward to the Renaissance. Through either Cuirassiers, Rifle/Cannon, Cavalry, or whatever, you've managed to get a lot of cities. Around this time, you've gotten techs like Nationalism, Constitution, and Democracy, which are key for Espionage players. Unless you have a mass of Cottages, you should switch out of Bureaucracy and into Nationhood, which is a powerful civic even if you don't use Globe Drafting. As I said in another thread: Also, if you haven't already you need to switch into Representation, which gives your Spies some additional research. This makes them pretty attractive specialists to run, and right now you can run 5 per city with all the buildings. Speaking of which, you need to get the Espionage buildings up. So build them, whip them, rushbuy them and go back to Rep later, I don't care. Eventually, you'll find your way to Communism, which gives you Intelligence Agencies. These give your Espionage a huge boost, and let you run up to 7 spy specialists! By now, you should be producing a pretty beastly amount of Espionage. The exact amount will depend on the game situation. Let's say that there's no Mansa or Pacal nearby, and you have to steal from Saladin. In that case, I wouldn't focus too much on Espionage. I would just build the Esp buildings, run some specialists, but focus on manual research, stealing backfill techs while I beeline others. Some players call this a "Hybrid EE". From my experience, I usually can get over 1000 EP/Turn without touching the slider or microing EP optimization, if I have a large empire. This is enough for a "Hybrid EE". Now let's assume that I AM next to Mansa or Pacal. In this case, I would go all out on Espionage. My Oxford City would run Spies instead of Scientists, I would use the slider for EP, and I would be mass-producing Spies (the units) to blow up Security Bureaus and steal techs. I would still be doing manual research from Rep-boosted Spies and multipliers, but most of my techs would come from robbing Mansa and brokering his techs to other people. So by the end of the game, my civics would be: Representation (for Research Boost) Nationhood (for EP Boost) Emancipation (to avoid ) Economic Civic of Choice OR/Theo/Paci (must maintain a State Religion) Spies or Scientists? Earlygame, Scientists are superior mainly because GS can bulb on the way to Liberalism, and you can build Academies. Also, you can multiply the research output of Scientists, and you can't do the same with Spies. Hell, you can't really run too many Spies anways. Lategame, Spies are almost always better, since you CAN multiply their Espionage output. Also you have Representation, which makes the research they put out (4 per specialist) comparable to Scientists. And Great Spies give 12 EP, which is massive. It costs 1.5 times as many EP to steal a tech as Beakers to research it. More with distance penalties. But Spies can get discounts by waiting 5 turns, running the religion of the city you're stealing from, and getting more EP. Stealing techs becomes more efficient than researching them, the only caveat is that an AI has to have the tech. How to Steal Security Bureaus are your enemy, they increase EP costs by 50% and increase the chance that a Spy will get caught. You need to destroy the Security Bureaus before considering any stealing. Or better yet, try to find crappy cities that won't have a Security Bureau to begin with and can't build one for a while. If the enemy is in FR, look for cities with your state religion so you can still get a 15% discount (25% with holy city). Always remember to account for the logistics of the situation. You may wish to steal from Mansa, but you can't feasibly do it if he's across the ocean unless your Spies never get caught or something. Speaking of Spies getting caught, more Spies in one city increases the chance of them getting caught, so be careful with the amount of Spies you put in one city. I like to blow up the Security Bureau, then put about 2 Spies in to get a pretty reliable chance of stealing techs. If the RNG screws you, you should be ready to make more Spies within a turn. Other Uses of Espionage: One good mission to use it "Sabotage Project". The main point of this is to ruin enemy's Space attempts. If you can find the Apollo City, you can also continually blow it up and nullify the enemy's Space chances altogether! Now let's address civics and religions. You can only swap the AI into your civics, so this only really comes into play when we're discussing economic civics. The AI loves Mercantilism, and by swapping them out of it you can get better trade routes for yourself. Or, if a large AI is abusing a Corporation, by swapping them into State Propery you can put their hard work to waste. Religion changes are more interesting. You'll want to switch people into your religion for an EP discount, and to mess up Diplo: make them your friend and someone else's enemy. This can be particularly huge with the Zealots. Traits for Espionage SPI Civs are the best because SPI is the best trait! Well, in my opinion, at least. Seriously though, SPI lets you swap into and out of civics and religions, which can be handy in Espionage-based games. The problem with FIN is that it's pretty pointless to play an Espionage game, since you should be Cottaging heavily and having a strong lategame. But one idea you can try is running Cottages everywhere, but making one Spy Farm with all the EP buildings and the Kremlin. The EP you make can be used to steal a few techs, or just blow up spaceship parts or revolt cities during a war. IND is an interesting trait for Espionage, since it synergizes very well with the hammer-heavy SSE-->EE playstyle. In layman's terms, this means: Wonderspam in capital, build 5 supporting cities. Turtle till Renaissance, then explode via war, and now you have a lot of cities. Then run Espionage buildings and Spy specs. You should try this with Ramesses II. PHI is cool for a few more Great Spies, and a fast Great Spy if you get the Great Wall, which can be really helpful earlygame. Other than that, basically any leader can use Espionage to their advantage, especially the leaders with poor economic traits that usually get large empires, like Genghis Khan. It helps to have a hammer-heavy empire to quickly lay down the EP buildings as they come in. TL;DR Espionage is fun. Espionage works well lategame with large empires and the Nationhood civic. Scientists are better early, Spies are better later. Blow up Security Bureaus before stealing techs, or pick cities without them. Anyone can use Espionage to their advantage. Final Note: Espionage is best used when you have a reason to use it. There's no reason when you're making 3000 beakers per turn, or have a heavily cottaged empire and are tech leader. The best reason to use Espionage is when you've focused on Specialists for most of the game, and would fall behind the AI's without stealing techs. I plan to add more info to this guide. Of course, all constructive criticism is accepted.