Describe a situation where you took extra steps to satisfy a customer and include the end result.

I described both a positive and a negative customer situation, so that you can demonstrate learning from past "mistakes;" in my case it was knowing when to ask for help. This also helped take control of the interview. The positive case example was related to efforts that directly mirror the current position: an in-person meeting with the customer and the sales manager to address concerns. The outcome was a new account (added to multiple existing accounts) and referrals for even more business.