Background: Our aim was to evaluate the effectiveness of an intervention to reduce the incidence of non-ventilator-associated hospital-acquired pneumonia (NV-HAP) and determine compliance with preventive measures., Methods: This was a quasi-experimental before-after study involving patients in the 53-bed Internal Medicine ward in a university hospital in Spain. The preventive measures included hand hygiene, dysphagia detection, head-of-bed elevation, withdrawal of sedatives in the event of confusion, oral care, and sterile or bottled water use. A prospective post-intervention study of the incidence of NV-HAP was carried out from February 2017 to January 2018 and compared with baseline incidence (May 2014 to April 2015). Compliance with preventive measures was analyzed with 3-point-prevalence studies (December 2015, October 2016, and June 2017)., Results: The rate of NV-HAP decreased from 0.45 cases (95% confidence interval 0.24-0.77) in the pre-intervention period to 0.18 cases per 1,000 patient-days (95% confidence interval 0.07-0.39) in the post-intervention period (P = .07). Compliance with most preventive measures improved after intervention and remained stable over time., Conclusions: The strategy improved the adherence to most of the preventive measures, with a decrease in the incidence of NV-HAP. Efforts to enhance adherence to such fundamental preventive measures are critical to lowering the incidence of NV-HAP., (Copyright © 2023 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)