Over the past few years, applications that allow telephone calls and video conferences over packet based networks have emerged. Originally used to place inexpensive long distance calls over the internet, some of these applications are now targeting business users and are meant to be used as video conferencing tools. New telecom firms that use the internet to place international calls are now emerging and many of the traditional carriers are testing IP telephony or plan to move their switching networks to packet based networks. In this talk I will describe the different applications and uses of IP Telephony, the direction where the industry is heading and what kind of products are needed to support this growth. I will also discuss the standards used in IP Telephony (H.323 / T.120 / SIP / RTP) and the problems that have yet to be solved.