E-cigarette use among young people has fallen for the first time in Wales, according to research by Cardiff University.
But the decline in 11 to 16-year-olds smoking has stalled, the study found.
The 2019 Student Health and Wellbeing Survey asked more than 100,000 pupils from 198 secondary schools across Wales about their smoking habits.
The findings show 22% of young people had tried an e-cigarette, down from 25% in 2017.
Those vaping weekly or more often had also declined from 3.3% to 2.5% over the same period.