Phone screenings are a great opportunity to look at factors that don't necessarily have to do with engineering at all: a candidate's personality, politics, and past experience. The first is simple; the interview as a whole will give you an idea of whether the candidate has a good attitude and is easy to communicate with.

Give your interviewees' resumes a careful read before the interview, and be sure to ask clarifying questions about a candidate's accomplishments during the interview. Asking a candidate to tell you about him or herself during the first part of the interview is a great strategy; as they walk you through their career history, ask specifically about what they wrote on their resume to guide the conversation. Good candidates will have a consistent story about their experience and will add relevant details.

Look for instances on candidates' resumes where they faced a challenge in an interpersonal or political sense: businesses or projects they founded...