Nowadays simulation is taking an important place in training and education of healthcare professionals. The University of Hertfordshire is carrying out a study which aims to determine the effect of realistic scenario-based simulation on nursing students' competence and confidence. This project is sponsored by the British Heart Foundation and takes place in the Hertfordshire Intensive Care and Emergency Simulation Centre (HICESC), a simulated three adult beds Intensive Care Unit. The simulation platform used is a Laerdal SimMan Universal Patient Simulator. A unique and robust study design, and results of the study are presented in this article. Consecutive cohorts of students are being assessed and reassessed after six months using an Objective Structured Clinical Examination (OSCE). Students are randomly divided into a control and experimental group for the period intervening between the two examinations. The experimental group is exposed to simulation training while the other students follow their usual nursing courses. Comparison is made between the OSCE results of the two groups of students. The experimental group had a greater improvement in performance than the control group (13.43% compared with 6.76% (p<0.05)). The results and feedback received from students and lecturers suggest that simulation training in nursing education is beneficial.