听力原文：I've called this meeting because, as you're all probably aware, we have some security issues in this building. There have been a number of thefts and reports of unauthorized persons wandering around the premises. So, we have some new guidelines to deal with this. Some of these are just common sense so, to begin with, can I ask you all to close any windows before you leave the building at night? From next month, all the office space will be air-conditioned and the windows will be sealed, so this will cease to be a problem. Next, the new I. D. swipe-card system will be in place from Monday, so if you haven't collected your card from Jenny, please do so before you go. What is the purpose of the meeting?