Nearly 2,000 swimmers from across Europe took part in the bi-annual event and Willison, 56, who lives in Bracklesham Bay and is a member of Bognor Swimming Club, represented Great Britain.
She was joined by 95 other GB masters and she entered the 55-59 years 200m individual medley, 100m butterfly, 50m butterfly, 100m freestyle and 200m freestyle.
Competition was particularly fierce from Russian, Ukrainian and German entrants, but Willison scooped three silvers and a bronze and notched three personal-best times.
She missed gold in the 100m fly and 50m fly by 0.8 of a second. The bronze was for the 100m freestyle and she came fifth in the 200m freestyle.
As part of her training with Bognor, Willison has a ‘remote’ trainer, Glen Christiansen, a Swedish breaststroke swimmer with multiple world records.
He emails her a weekly training programme. Half her training is done at Westgate Leisure in Chichester, the other half at Bognor, where she joins the juniors under the eye of coach Sue Eason.
Willison’s next event is the GB British Gas Masters National event at the end of October, followed by the World Masters Swimming Championships next June in Riccione on the Adriatic coast of Italy.