When you play a game, something happens. You might be feeling elated, frustrated, engaged, furious, whimsical. Your heart rate might go up, and your sweat glands activate. Alpha- and beta-waves firing in your brain. You are having an experience. The user experience we get from playing games is called "playing experience", and it is the alpha and omega in games user research - or "GUR" - which exists to ensure that players experience games in the way the designers expect them to. However, as important as player experience is to GUR, we have a hard time figuring out exactly what it is or how to measure it. In this inaugural episode of the Games User Research Podcast, we have a conversation about player experience: what it is, how to measure it, and why that measuring is enormously challenging.