Alyson Shontell writes:

When new employees start at Jack Dorsey's payments company, Square, they receive a welcome kit.

The welcome kit comes in the form of a sleek black box. In it, there's a square-shaped pamphlet that explains "The Four Corners Of Square"—a set of principles for the company:

1. We start small
2. We collaborate in commons
3. We round the square
4. We craft the entire span in a breathtaking way

There's also a Square credit-card swiper, a Field Notes notepad, and a big red book.

The big red book is a piece of literature Dorsey often quotes called "The Checklist Manifesto: How To Get Things Right."

Dorsey now gives it to everyone he employs.

The "Checklist Manifesto" was written by Atul Gawande, a doctor and writer for the New Yorker. Its premise: A simple checklist can help people manage complex situations. Gawande uses a number of examples across a variety of industries, from medicine, technology and even disaster relief to illustrate his point.

"Success metric for my work @Twitter: these books disappear from my desk. (you should read it too)," he tweeted in April.

He particularly likes this passage about venture capitalists choosing which startups to invest in. He quotes it on his Tumblr:

"Smart specifically studied how such people made their most difficult decision in judging whether to give money to an entrepreneur or not. You would think that this would be whether the entrepreneur’s idea is actually a good one. But finding an idea is apparently not all that hard. Finding an entrepreneur who can execute a good idea is a different matter entirely. One needs a person who can take an idea from proposal to reality, work the long hours, build a team, handle the pressures and setbacks, manage technical and people problems alike, and stick with the effort for years on end without getting distracted or going insane. Such people are rare and extremely hard to spot."

- Atul Gawande, The Checklist Manifesto

Andrew Borovsky is the cofounder of 80/20, a design agency, which Square recently acquired. Borovsky put the picture of his welcome kit on Instagram, shown above.

More insight into the mind of Jack Dorsey.

A tour of Square's office:

http://www.businessinsider.com/square-tour-2010-9?op=1