It’d be easy to assume that this negative-sounding question has been asked to trip you up in order to reveal your deficiencies so that the interviewer can figure out if you’re up to the job. Not so. Instead this question is designed to test your ability for self-analysis; the interviewer will be looking for a positive yet honest response. But rather than give a ‘warts and all’ answer focus your response on an area that doesn't have a major impact on your ability to do the job and/or an area that you are on your way to improving (not an area you've already improved, but one that is well on its way). You can also use positive weaknesses as mentioned earlier.