You will generally be asked this question only if you are applying for a position driving a city bus. In larger cities, buses run well into the night—sometimes even 24 hours a day. You may be given a midnight shift due to your lack of seniority, or scheduling may require that you work swing shifts. This is not the time to discuss your personal scheduling needs, however. Replying with a statement such as “I do not mind working nights or weekends and I am always available” will suffice. This is exactly what your potential employer wants to hear since your flexibility will help the bus system stay on schedule.