Interviewing is time consuming, companies have a finite amount of time to dedicate to recruitment and inevitably some capable candidates are turned down at CV stage without ever having a chance to shine.

Phone screens are a great way to address this problem, they are typically shorter and often run solo. They allow a company to take more risks and consider candidates from further afield.

My company is still pretty new to phone screening, we’ve been trialling it out in cases where it is difficult for the candidate to attend in person – perhaps they are based overseas. As a result I’ve been doing a lot of reading on how best to construct a decent phone screen. By far the best writing I’ve found is Steve Yegge’s take. I’m not sure how practical it is to fit everything Yegge mentions into a 45 minute call, but I consider it an excellent resource.

A common fear I have seen in other discussions seems to be that candidates will use google to somehow game the system. If this is a genuine concern then one of two things has gone wrong. Either:-

The questions are purely fact based and will tell the interviewer nothing about how the candidate thinks.

Or, the questions are fine but the interviewer is focusing on the wrong part of the answer.

A question like ‘In Java what is the difference between finally, final and finalize’ will tell you very little about the candidate. Plenty of terrible programmers could answer that without problem and what’s worse, a talented but inexperienced developer might stumble. In short these type of quick fire questions add little value to the overall process.

Something like ‘How does a Hash Map work? How would you write a naive implementation?’ is more interesting, it’s open ended but forces the candidate to talk about a specific area of knowledge – even if they don’t know, you’ll learn how good they are at thinking things through from first principles. The only way that it can be gamed through googling is if the interviewer simply waiting to hear specific terms and is not asking free form follow ups.

I’ve just googled Hash Maps on wikipedia and could probably quickly extract ‘Associative array’, ‘key-value pair’, ‘Collision’ but really if that’s all the interviewer wants to hear then the question is of limited value.

So what I’m saying is that if you’re concerned about googling, then it’s probably the questions or desired answers that are the problem. Furthermore if one in a hundred people do manage to game the system you’ll pick them up in the face to face in an instant.