Background: Tobacco use among young people in Ireland is declining but remains a problem. The use of e-cigarettes is increasing and its implications unsure. In our previous Irish study, 23.8% (n=196) of respondents had used e-cigarettes at least once and 4.2% of never smokers had used e-cigarettes (Babineau, K. et al. (2015) PLoS ONE 10(5)). Design/Methods: A cross-sectional, nationally-representative survey was conducted with 2028 young people aged 15-17 as part of the European School Survey Project on Alcohol and Other Drugs (ESPAD). This included 4 items on e-cigarettes as well as several items on smoking behaviours and attitudes. Results: 24.7% (n=482) reported use of e-cigarettes at least once, including 214 students who reported using e-cigarettes in the last 30 days (11.0%). 130 students reported daily use of e-cigarettes (6.8% of sample). 18.3% of e-cigarette users (n=88) cited quitting tobacco as a reason for using e-cigarettes. The most common reason for using e-cigarettes was “out of curiosity” 61.2%, (n=295). 8.3% of never smokers had used e-cigarettes (n=109). 13.4% (n=272) reported that they had smoked one or more cigarettes in the last 30 days, 6.9% smoked daily (n=139). Two-thirds of students (66.7%, n=1,350) reported that they had never smoked a cigarette. Conclusion: E-cigarettes are popular among youth in Ireland, with around a quarter of respondents reporting they had used e-cigarettes. E-cigarettes are now used as commonly as cigarettes. Even more worrying is the finding that there has been an almost doubling of e-cigarette usage among never smokers in the current study. The implications for future smoking is unknown but nicotine addiction seems set to continue.