This classic book on human psychology has many imitators. It's a joy to read and shows how and why people do the things they do, based on six principles, including: Reciprocation (if you give something, the other person is wired to return; Social Proof (see what others have done before we act); and Liking (which probably speaks for itself!). Influence is one of the most recommended books by business leaders. See why...

From the founder of growthhackers.com comes this helpful guide for startups to, er, grow. With an easy writing style the authors go into how every company should go about it; namely building specific growth teams which cross divisions and departments. But which project should you work on first? The authors help your team work out logically and methodically, which projects to work on first, while always testing, testing and testing.