Background: Critically ill patients in critical care units (CCUs) are at high risk for infections associated with increased morbidity, mortality, and health care costs. The overall infection rate in critically ill patients approaches 40% and may be as high as 50% or 60% in patients who remain in the CCU for more than 5 days. Ventilator-associated pneumonia (VAP) in mechanically ventilated patients ranges from 8% to 28%. VAP refers to an infection that develops during mechanical ventilation after 48 hours of intubation. ­Nurses play a pivotal role in decreasing patients' risk of acquiring VAP. Keeping pace, in this instance, is really about turning focus back to the more basic aspects of critical care nursing. Evidence now demonstrates how important basic nursing care is to the prevention of VAP by using strategies for the prevention of VAP. Objective: The aim of this study was to assess nurses' compliance of evidence-based guidelines for preventing VAP in CCUs. Methods: The study was conducted at the CCUs of Alexandria Main University Hospital namely, Casualty Intensive Care Unit (unit I) and General Intensive Care Unit (unit III). The sample of this study consisted of 60 nurses working in the previously mentioned CCUs. Two tools were used for data collection VAP Preventive interventions Observation Checklist (VAPPIOC) and VAP knowledge questionnaire (VAPKQ). Results: Nurses had different levels of adherence for many non-pharmacologic strategies. All nurses responses to the questionnaire, rates and reasons for non adherence were addressed. Conclusion: The most important barriers to implementation were environment-related. Other reasons for non-adherence were patient-related barriers being significantly important for nurses. Overall, the most important barriers to adherence were unavailability of resources. Our findings suggest the need for development of guidelines to reduce variability and the need to include the nursing point of view in these guidelines.