Your answer to this question conveys a bit about your personality and sense of responsibility. Interviewers know that most companies want employees to give at least two weeks notice prior to their departure. The fact that you’re interviewing with a potential new employer indicates that you intend to leave your current position. So expressing that you want to follow appropriate protocols for departure indicates that you respect the way things should be done. Hopefully your current bosses do not yet know you intend to leave, and even if they did know, they might not say anything until you make a formal statement. Tell your interviewer that you hope you can put off the start date of a new position so that you can give proper notice to your current employer that will allow at least some time for the recruitment of your replacement. And if a replacement candidate is already in the pipeline, you would possibly participate in their initial training or orientation. This tells the new employer that you care about the people you work for, and are committed to doing things right.