There is your answer right there, you should not visit houses on your own, when you work with an agent, unless you both have agreed differently. In that case your agent should give you couple of her business cards. Some selling centers specifically request that an agent must accompany a client at the 1st visit and register the client. All clients should be careful when approaching open houses. This is the listing's agent chance to find a client on her own, so she doesn't have to give up part of her commission. On the other hand it is not your fault. You are not a pro in this profession. First of all your agent should educate you, so you don't run into situations like this in the future. Second, the listing agent didn't behave professionally, nor ethically. When you told her that you work with an agent, she should write it down and ask about your agent's name, or even a business card. You are right to worry about your agent's commission because she is working hard for you, and she is working at this moment for FREE, right? You don't pay her for showing you houses, so it is only fair that when she helps you find a house, she should get paid. And because it is not coming out of your pocket, you should be double careful and loyal to your agent. Regarding that specific situation, I am afraid, that even if your agent puts an offer for you on this house, she won't get paid. It is called a procuring cause. The best you can do is to ask your agent to talk to her broker, so he or she can call the other agent's broker and discuss this before you present an offer. This might help to protect your agent's interest in the cooperative compensation. Good luck!