This question is designed to determine if you can function well in a competitive environment. Think back to a time when you were racing others to achieve the highest sales, were working towards a promotion, or eagerly trying to win a new contract. Show the interviewer that you rose to the challenge and that you were excited to push yourself to be the best. It is a definite plus if you have cheered on your competitors and helped them along the way. Finally, be sure to mention any successful outcome.