Pair Programming
Code that is written by two people who sit next to each other at the same computer is pair-programmed code. That code is considered high quality and should result in cost savings due to less maintenance.
In the long run, this style of development saves money because fewer bugs are written and therefore do not need to be fixed later.
An indication that pairing is beneficial and should be done more often is the following example:
When you are writing an important piece of code, don't you want another person to look it over before it goes into production?
While we don't pair program 100% of the time, there is no better collaboration between designers, developers, or between designers and developers than at the keyboard.