Depending upon your employer, you may be asked to maintain an 'on-call' status 24 hours a day. If you are applying for a position with a large corporation, you may split this responsibility with other bookkeepers. However, if you are applying for a position with an individual or a small business, you will likely be the only bookkeeper. As a result, should an emergency arise, you will need to be available. To answer this question, reply with, I understand that my expertise is very important to you as my employer. I will be available around the clock to resolve any issues or answer any questions that may arise.