Grapevine
The Grapevine is the network of rumors that drive the illicit trade in booze. Customers hear about speakeasies, and operators about each other through the Grapevine.
Your reputation dictates from how far your Grapevine extends. When two operators' Grapevines overlap they can hear rumors from and make offers to each other.
The grapevine operates on the grid of the city.
Above is part of a grapevine you might see in the game.
Your operation is green. Other players' are brown. In the game clicking on an operation will show you information about it.
The faded section to the left is currently outside your grapevine - you know there are operations there but you cannot do business with them yet.