Introvert Susan Cain is here to make the case for people who like to work in peace and quiet. Today's workplaces are designed for extroverts, she says, and put too much emphasis on group work. Cain's new book is called Quiet: the Power of Introverts in a World that Can't Stop Talking.

The desire to find our tribe is universal. We like to know who we are and where we belong. This fascination has led to a thriving industry built on the marketing and sale of personality tests. These tests offer individuals - and, increasingly, employers - quick and easy insights that can be used ...