External ventricular drains (EVDs), like any surgically-implanted foreign body, are at risk of infection. We present the results of a completed audit loop following introduction of an evidence-based protocol for their insertion and management. There were two phases over a 2-year period. Phase 1 was a retrospective audit of our EVD infection rate. Phase 2 was a prospective audit of the infection rate subsequent to the introduction of a protocol for the insertion and management of EVDs. In phase 1, the infection rate was 27%. In phase 2, the infection rate was 12%. This was a statistically significant reduction (p < 0.05, Chi-squared test). EVD infection is unfortunately a common clinical problem and associated with potential morbidity and mortality. This study demonstrates that adherence to an evidence-based protocol for their insertion and management is associated with a significant reduction in the infection rate.