Baryon number is an accidental symmetry in the Standard Model and is thus fundamentally expected to be broken. In these proceedings, we summarize the current status of this topic. We review the latest experimental bounds on nucleon decay, the most sensitive probe of baryon number violation, and discuss future prospects. On the theoretical side, we outline the key conceptual steps in computing nucleon decay rates and explore how baryon number violation arises within Grand Unified Theories (GUTs). Finally, we highlight the challenges in making robust nucleon lifetime predictions within GUTs and propose possible strategies for their mitigation.