How to Employ effective mid-game strategies when playing Civilization V

So you've set up your civilization, have started producing a few resources and built up a solid base. Now it's time to delve into the more complex aspects of Civilization 5 - dealing with things like economy and diplomacy. This tutorial delves into a few of these advanced concepts to ensure an effective and strong mid-game.

(1) Part 1 of 5 - How to Employ effective mid-game strategies when playing Civilization V, (2) Part 2 of 5 - How to Employ effective mid-game strategies when playing Civilization V, (3) Part 3 of 5 - How to Employ effective mid-game strategies when playing Civilization V, (4) Part 4 of 5 - How to Employ effective mid-game strategies when playing Civilization V, (5) Part 5 of 5 - How to Employ effective mid-game strategies when playing Civilization V