I’ve grown my companies by focusing on great customer service. We didn’t always have the biggest names in business working at the firm, and we sure couldn’t always afford the flashiest equipment. What we did better than all our competitors was ensure that our customers were thrilled.

In fact, superlative customer service can be your very best (and cheapest!) form of marketing. Customers talk about their experiences, especially if they’re unexpectedly good. Sometimes even the most difficult situations can yield satisfied customers, depending on how you and your team handle the problems that arise. Even a failure to meet expectations can offer an opportunity for a great recovery and a happy customer.

Here are four phrases that will help you bring up the level of service your customers receive:

1. “I don’t know, but this is what I’m going to do.”

You’re not always going to have the answer to every question at your fingertips, and your customers will understand that. What they expect in exchange, though, is honesty and follow-up. The key here is to make a clear commitment like,” I’ll call you by 5pm with the answer,” and then keep that commitment! Even if it’s taking longer to get a problem resolved or to get the answer to your question, follow up with customers to let them know you’re still working for them. Customers want you to be honest and to keep your word. If you promise to call by 5pm, then you must call by 5pm, or you’ve betrayed your customer’s trust, and you’ve let that customer down.

2. “I am very sorry.”

When you or your company has made a mistake, the customer wants to hear you accept responsibility and apologize. Too many customer service reps have been trained not to accept responsibility, in some cases because they fear the legal record of having admitted failure. Realistically, though, the probability of a lawsuit is minimal, while the chance of losing a customer is virtually guaranteed. It’s important to manage the unhappy customer’s expectations while you apologize, though. Be genuine, and save your apologies for the instances when your company has truly made a mistake, rather than apologizing to every customer displeased by circumstances that are beyond your control. The apology is only a step, albeit an important one, and the goal is to turn the failure into a success by determining what your company can do to make it right.

3. “Yes.”

“Yes” is what your customer wants to hear, and your goal should be to say that word whenever possible, even if – especially if – you’re working through a problem. Customers want progress. Imagine two scenarios: Customer 1 calls with a complaint and asks for a 10% discount. The customer service rep says no, finally hands the customer off to a manager, and twenty minutes later you have an angry, frustrated customer with a 10% discount from the manager. Customer 2 calls with a complaint, and the customer service rep apologizes and offers a 10% discount. The cost to the company – 10% — is the same, but call #1 took longer, involved two staff members, and left a customer feeling frustrated rather than satisfied. Call #2 yields a customer who truly believes that your company cares about their business. Say yes to reasonable requests as soon and as often as possible, and leave your customers pleasantly surprised at how easily the problem was resolved.

4. “Is there anything else I can do for you?”

Here’s your perfect wrap-up. Not only does this question give your customer the opportunity to bring up additional concerns, but it also lets the customer feel like they’re in control. They can ask for additional information or they can thank you for your spectacular service. Giving your customers the opportunity to raise additional concerns lets them know that you value them enough to spend time ensuring that they’re satisfied. Even if the customer called with a problem, if your customer service team can work through a resolution and end on a positive note, you can earn and keep those customers for life.

Great customer service relies first and foremost on authenticity. You and your team must be committed to satisfying your customers, and being trustworthy is the foundation. If your customers trust you to keep your word, then you’re more than halfway there. If your customers know they can rely on you, even if there’s a problem, that’s the rest of the journey.

Work on training your customer service reps to listen, determine what the customer expects, and do what they can to make sure that customer is satisfied.