For engineers and subject matter experts actively engaged with 5G voice, this course offers a deep dive into call flows and messaging/signaling related to evolved packet system fallback (EPS-FB). The concepts covered in this course are intended to help engineers understand what to look for in user equipment (UE) and network traces when deploying, debugging, and optimizing EPS-FB. This half-day course uses UE logs to discuss signal registration and establishment of data and voice during Packet Switched Fallback.