What do I look for when building a team?

I've shuffled the priority of these hiring criteria over the years, but this list has served me well:

1. Very high level of professional and personal integrity.  This is profoundly difficult to measure in an interview, but it is the primary value of hiring people with whom you have previously worked and now trust. 
2. Intellectual brilliance.  I'm living proof of how someone can compensate for his shortcomings, but you must surround yourself will the brightest people you can attract to solve the great challenges your business will face.  Aspire to be the dumbest guy in the room.  I've often described this quality as hiring intellectual athletes.  A candidate's work experience might not be precisely what you were seeking, but a keen intellect and a willingness to take on new challenges are much more valuable.
3. Great student.  Loves to learn new things every day.
4. Great teacher.  Loves sharing their knowledge to help others succeed.
5. No jackasses. This is not the same as "no ego" or "team player."  Life is just too short to work with jackasses no matter how valuable you might think they could be to your business.
6. Great work ethic.  Great technologists and business people work hard because they enjoy the challenges and want to succeed.