The influence of the inanimate hospital environment and hospital design on nosocomial infection is a topic for discussion. This study evaluated the impact of the neonatal intensive care unit (NICU) environment on the risk of hospital-acquired infection (HAI). HAI surveillance was performed during a four-year period when the NICU was moved initially from an old facility to temporary accommodation and then eventually to a new and better-designed facility. The rate of HAI rose significantly from 12.8 to 18.6% (P<0.01) after moving to the temporary unit, which had a lower sink:cot ratio and a higher monthly admission rate. In contrast, the rates of catheter-associated staphylococcal bacteraemia decreased significantly after moving to the new NICU (P<0.0001). Since peripherally inserted central catheters (PICCs) were introduced concomitantly with the move to the new unit, however, the catheter type may have contributed towards this reduction in CVC-related staphylococcal bacteraemias. Moving to a temporary NICU with poor handwashing facilities and higher admission activity resulted in higher rates of HAI.