This chapter evaluates the energetic impacts of various internal bubble energy components, including pressure–volume (PV) work, reaction heat, heat transfer, and mass transport, under diverse acoustic conditions across different cavitation scenarios. Furthermore, the energy dynamics within a multibubble system are examined, with a focus on estimating the bubble population and the cumulative energy contribution of the system. At the single-bubble level, an analysis of the two main phases of a bubble’s lifetime, rarefaction and collapse, reveals that PV work, driven by external liquid pressures, plays a significant role in augmenting internal bubble energy. However, substantial energy dissipation occurs through thermal conduction and mass transport via condensation at the bubble wall, with thermal conduction emerging as the dominant loss mechanism. At the multibubble scale, the influence of these energy parameters during expansion and collapse phases appears largely independent of ultrasound frequency, in contrast to observations from single-bubble studies.