This time I want to suggest a Book. It's How to Win Friends & Influence People by Dale Carnegie (you can find it also on Amazon).
If you wish to work with people, you should know how to communicate with people.
Game developers are usually supported by Middlemen - Account planners, managers, etc. ones with a more developed social component.
This book is a door for a deep insight into customer relations and service providers.
You should read and browse every year in it.
It upgrades people with normal social skills to have super social skills - what leads to open doors.
How to Win Friends and Influence People is one of the first best-selling self-help books ever published. Written by Dale Carnegie (1888–1955) and first published in 1936, it has sold over 30 million copies world-wide, and went on to be named #19 on Time Magazine's list of 100 most influential books in 2011.