Chats are roulette style that match you with the first participant available, so you do not have to choose a participant to chat with. If you do not need the full amount of time to chat, you can excuse yourself and click "End this chat," to end the conversation.
SmartQueue is a proprietary screening technology that asks participants a series of questions and prioritizes them based on their responses to those questions. If SmartQueue technology is enabled for your event, participants with higher SmartQueue scores will be prioritized so that you can speak with them first.
For Open House and Expo events, on the ratings screen you will have the option to allow the participant to chat again with other representatives in your booth.