This study investigates the effect of vapor content on the collapse dynamics of laser-induced cavitation bubbles in aqueous ammonia. The researchers found that higher vapor pressure in more concentrated solutions acts as a resistance to the collapse, reducing the total energy dissipation. Visual observations, acoustic measurements, and luminescence recordings revealed that higher vapor pressures contribute to a more spherical collapse, likely by decreasing collapse velocities and accelerations. The study also evidenced a strong difference between the effective damping and the energy of the shock emission, suggesting that the latter is not the dominant dissipation mechanism as predicted by classical models. The findings provide insights into the influence of bubble content and energy exchanges with the surrounding media, which could have implications for engineering and biomedical applications. The results highlight the importance of vapor compression during the collapse and suggest that vapor inside collapsing bubbles gets compressed, addressing the question of whether vapors readily condense during collapse in similar regimes.This study investigates the effect of vapor content on the collapse dynamics of laser-induced cavitation bubbles in aqueous ammonia. The researchers found that higher vapor pressure in more concentrated solutions acts as a resistance to the collapse, reducing the total energy dissipation. Visual observations, acoustic measurements, and luminescence recordings revealed that higher vapor pressures contribute to a more spherical collapse, likely by decreasing collapse velocities and accelerations. The study also evidenced a strong difference between the effective damping and the energy of the shock emission, suggesting that the latter is not the dominant dissipation mechanism as predicted by classical models. The findings provide insights into the influence of bubble content and energy exchanges with the surrounding media, which could have implications for engineering and biomedical applications. The results highlight the importance of vapor compression during the collapse and suggest that vapor inside collapsing bubbles gets compressed, addressing the question of whether vapors readily condense during collapse in similar regimes.