Heather O'Brien scored the crucial try as Ireland Women made it two wins from two
Wales, who were downed at the last by Italy last weekend, led 6-3 at the interval but back came Ireland through No.8 O'Brien and the boot of recalled full-back Niamh Briggs.
In difficult conditions it was never going to be a repeat of their record 59-0 opening victory over Scotland but it maintains Ireland's impressive start to the defence of their crown and keeps them on track for a second straight Grand Slam.
Jenny Murphy made an early break for Ireland but that aside, Wales' defence was resolute and it was the visitors who opened the scoring thanks to a Robyn Wilkins penalty.
And on 24 minutes, Wilkins' doubled her side's advantage - just reward for some impressive physical play from Wales, led by centre Rebecca de Filippo.
Crucially however, Ireland registered their first points of the evening just before the half-time interval through a Briggs penalty and after the turnaround at the break, they were to enjoy the wind at their backs in the second half.
Some clever positional kicking from Briggs kept Ireland on the front foot and they were level when Welsh indiscipline crept in and the full-back nailed the penalty - Lowri Harries being sent to the sin bin for a high tackle on Lynne Cantwell.
Ireland surged ahead thanks to O'Brien's try on the hour mark - the back row gathering loose possession and forcing her way over - and while the conversion was missed, Briggs added a late penalty to see off Wales.
