I was riding a shuttle to the airport after attending a marketing conference for entrepreneurs. The 20-minute ride flew by as I engaged in a lively conversation with “Nathan,” a fellow attendee I’d met the evening before at a networking event. As the shuttle pulled up to the terminal for Nathan’s flight, we exchanged business cards and agreed it would be a great idea to stay in touch.

Nathan handed the driver his credit card to pay the $20 fee. The driver explained that he couldn’t take credit cards, that Nathan would have to go to the shuttle ticket counter to make payment. But my new acquaintance was running late, so he turned to me and asked, “Can you loan me $20? I’m going to miss my flight if I have to go way over there and buy a ticket!”

I hesitated for a moment. Could I trust him to pay me back?

I’d just met Nathan and knew very little about him. He’d been talking about the success he was having in his business and I concluded it was a low risk. It was only $20, after all, so if he didn’t end up sending me the money, it was no big deal.

I dug my wallet out of my purse and handed him a twenty dollar bill. He said “Thanks so much,” gave the money to the driver and hurried into the terminal.

A few weeks went by and I heard nothing from Nathan. Then one day he called and said, “Hey, I owe you money! Where should I send the check?”

I gave him my mailing address, and he thanked me again for bailing him out at the airport that day. The check arrived within a couple of days and the next week I deposited it.

I felt good about my decision to help Nathan out…and about him… that is, until I got a notice a few days later saying that his check had bounced and my bank had charged a $10 fee to my account. So now I was out $30!

I called Nathan and told him what happened. He sheepishly responded, “I know.”

You know?! You mean you already knew the check had bounced and you didn’t have the guts to call and tell me? You took the coward’s way out and let me find out from my bank so I had to call YOU? What were you thinking?! 

I screamed all this inside my head, not to him. Because his next words were, “I’m not very good at managing my money. It turns out I didn’t have enough cash in my bank account to cover the check.”

How could you send a check to someone you hoped would refer prospective clients to you - and not be certain if the money was in the bank? Do you have any idea what kind of impression you’ve just made?

What I actually said, after taking a deep breath, was, “Gee, Nathan, that’s too bad. What needs to happen now is for you to send me a cashier’s check or money order for $30, to cover the $20 you owe me, plus the $10 bank fee. I’m not willing to risk getting another personal check from you. I’m sure you can understand.”

“Yes, of course. I’ll get that to you right away,” he assured me.

Two weeks passed. Nothing. 

I left a voicemail message and also emailed him. No threats, no angry words, just a reminder that I was expecting a cashier’s check or money order and had not received it.

No response.

It was no longer a matter of the money. It was the principle. His actions violated one of my core values: Honor your promises. Do what you say you’ll do. 

Two weeks later I left another voicemail and emailed him again. This time he actually called back.

“I mailed the money after we spoke last time. You didn’t get it?”

“No, Nathan, I didn’t. You’ll need to send it again,” I said flatly. I didn’t believe him. His previous behavior caused me to have no faith in his words.

He promised to put it in the mail right away, which confirmed my suspicion that he’d never sent it in the first place. It took another month but I did eventually receive his check.

Do you think I’ll ever send any business his way?

You may be shaking your head, thinking, I’d never do anything like that.

Yet there are hundreds of moments in your own life where you prove to others through your actions that you’re trustworthy—or not.

• You say you’ll meet someone at 1:00 for lunch, and you arrive twenty minutes late because you didn’t plan well or consider the impact on that person.
• You agree to call someone you met at a networking function, but you never get around to it.
• You tell a colleague that you’ll complete your part of a project by a certain time, but you miss the deadline because you procrastinated.

Think carefully before you make commitments that will affect someone else. Your relationship and your reputation depend on your integrity. Use this wisdom from Warren Buffet as your guide: