The aim of the study was to explore advanced life support (ALS) skills and knowledge retention, in 10 registered nurses, at 6 and 12 weeks following an in-house core ALS course. Data was collected by structured interview and structured observation at 6 and 12 weeks following the course. A sharp decline in the number of subjects attaining the 84% pass level at the 6 and 12 week interviews was noted. A modest increase in ALS theoretical knowledge and a decrease in practical skill performance between 6 and 12 weeks was identified. Implications for future practice and research are proposed.