The reporting of healthcare-associated infections is an action-oriented early warning system established by regulation in 2001. While the added value of this system in terms of health safety has been demonstrated, several evaluations conducted by the Centers for the Coordination of the Fight Against Nosocomial Infections (CClin) or the French Institute for Public Health Surveillance (InVS) have shown that its operation was not optimal. A qualitative evaluation was therefore conducted in 2009 to better understand the dynamics of its operation in healthcare facilities (HCFs) and propose avenues for improvement. It was commissioned by Raisin to a sociologist and was based on observations and semi-structured interviews with healthcare professionals from 12 HCFs in the West and Southwest regions and several national experts.The study highlighted varied reporting dynamics, organized around two pillars (Clin president and operational hygiene teams (EOH)) with limited integration into risk management. The barriers to external reporting were primarily those of internal reporting: debate over the nosocomial nature of the infection (diagnostic difficulty, association with negligence), low involvement of clinicians or paramedical staff, a negative perception of the system, or dissatisfaction with certain EOHs. The reporting system also suffered from a lack of clarity, suitable tools, and clearly defined objectives. Conversely, several factors appeared to facilitate good reporting practices: the presence of motivated professionals, the proximity of healthcare facilities to clinical departments, the automation of alerts within healthcare institutions, or the acceptance of quality metrics. This study suggests several avenues for improvement: increasing the transparency of the system by clarifying its objectives and procedures and by refining the definitions of nosocomial infections; adapting its implementation to on-the-ground realities; strengthening training for healthcare facilities; and developing forums for professional exchange. The recent implementation of formalized feedback mechanisms by the CClin and the digitization of reporting (e-SIN) led by the InVS are steps in this direction. (R.A.)