The study investigates the role of the *agr* quorum-sensing system in the formation and dispersal of *Staphylococcus aureus* biofilms. The *agr* system, which modulates virulence factor expression through autoinducing peptides (AIPs), is found to be necessary for biofilm formation but triggers detachment when reactivated in established biofilms. This detachment is dependent on extracellular proteases, particularly serine proteases, and can be inhibited by protease inhibitors. The findings suggest that the *agr* system acts as a regulatory switch between planktonic and biofilm lifestyles, and that its activation triggers a protease-mediated mechanism for biofilm dispersal. Additionally, detached cells regain sensitivity to antibiotics, indicating a potential therapeutic target for biofilm infections. The study also explores the role of PIA (polysaccharide intracellular adhesin) in biofilm detachment, finding no significant impact. Overall, the research highlights the importance of the *agr* system in controlling biofilm formation and dispersal, providing insights into the complex dynamics of *S. aureus* biofilms.The study investigates the role of the *agr* quorum-sensing system in the formation and dispersal of *Staphylococcus aureus* biofilms. The *agr* system, which modulates virulence factor expression through autoinducing peptides (AIPs), is found to be necessary for biofilm formation but triggers detachment when reactivated in established biofilms. This detachment is dependent on extracellular proteases, particularly serine proteases, and can be inhibited by protease inhibitors. The findings suggest that the *agr* system acts as a regulatory switch between planktonic and biofilm lifestyles, and that its activation triggers a protease-mediated mechanism for biofilm dispersal. Additionally, detached cells regain sensitivity to antibiotics, indicating a potential therapeutic target for biofilm infections. The study also explores the role of PIA (polysaccharide intracellular adhesin) in biofilm detachment, finding no significant impact. Overall, the research highlights the importance of the *agr* system in controlling biofilm formation and dispersal, providing insights into the complex dynamics of *S. aureus* biofilms.