General Colin Powell in his Leadership Primer says that:

“Organization doesn’t really accomplish anything. Plans don’t accomplish anything, either. Theories of management don’t much matter. Endeavors succeed or fail because of the people involved. Only by attracting the best people will you accomplish great deeds.”

So, how do you attract and choose the best people to work in your organization? What are the qualities that you look for when hiring people - is it the length of their resume, their past positions, their degrees or where they obtained them? Is it their familiarity and expertise with the specific technology or domain that the company needs at the moment?

While I consider their ability to do the work required to be important, I weight factors other than technical knowledge far higher. Technical knowledge and ability to learn new related skills is a threshold trait that just gets them the interview.

What I am really looking for in a candidate are qualities like enthusiasm, drive, and motivation - remember the adage that the team is only as strong the least motivated individual. I look for people who accept responsibility to get things done and don’t waste their time bitching and moaning about others and the circumstances they were in. Ultimately, a person’s talent is immaterial if he doesn’t have the desire to get things done. Equally important is the person’s ability to execute and not just talk a great game; don’t assume that if someone can think and plan and sell their idea that they can also execute and deliver.

A willingness to do new things is critical - generalizing specialists are more versatile than specialists and can contribute in more areas. How often have you had to deal with people who think of themselves as one specific role (for example, I am an Architect and that’s what I do)? That sort of thinking is really counter to the Agile way. It reduces flexibility in scheduling projects, exacerbates the functional silo mentality, and encourages department managers to optimize their function often to the detriment of the whole. Keep in mind that a team members job is to get the product out the door not to do just development, or just testing, or just requirement gathering.
You also want to hire people who can organize and plan their work and then execute it properly. If you don’t pay attention to this you end up hiring people that require constant baby-sitting and you end up doing most of their work anyway. If they demonstrate good judgment and an ability to anticipate problems so much the better.
Last but not least, look for people who are able to collaborate and work closely with others. I don’t want “team players” who just go along with everyone; I like people who are willing to express their opinions and disagreements but who also have an open mind to take in new information and reconsider their position if need be.

People with the right attitude are far more productive and easier to work with than prima donnas who just excel in one narrow activity. People with the right attitude can pick up additional skills fairly easily; training someone without these skills is far harder.
Ask the candidate to describe the accomplishment that they are most proud about. Then ask probing questions and listen for clues to the above in their responses. Also, ask what they would do once they got the job; their responses will let you know whether they have thought out a plan and how they would execute once on the job.