This report explores the effect ambient lighting systems has on immersion in games as well as the definition of immersion and how it can be measured. A semi-structured interview is used to establish the meaning of immersion according to ten Danish gamers. The collected data is analysed through grounded theory and the results used to devise an Immersion questionnaire. The questionnaire was used in an experiment to examine whether playing games with an ambient lighting system has an effect on the players immersion. This was done by exposing 16 participants to three different ambient lighting conditions. The experiment was video recorded and followed by a questionnaire. The results from the experiment revealed no statistically significant difference between the conditions.