Alliance Party deputy leader Stephen Farry has told the party's annual conference in Belfast that people in Northern Ireland are moving away from traditional labels.
He attributed the party's success at the recent UK general election to people expressing open, mixed and multiple identities.
Mr Farry, who won the North Down Westminster seat in December's election, made the keynote address after party leader Naomi Long was diagnosed with a respiratory infection.
Mr Farry added: "People are often asking what were the factors behind Alliance's success?
"For starters, Northern Ireland is a changing society, and changing more quickly than many appreciate."
Mr Farry said that the "old canard" of a vote for Alliance was a wasted vote has been "shattered".
"We have proven that we can win anywhere in Northern Ireland and we have drawn votes from right across the community," he added.
"We have proven that in a political context usually framed around the constitutional question and a clash of identities that a liberal and cross-community party cannot only survive but flourish.
"While we have broken the glass ceiling, there can be no room for complacency or sitting back on our laurels.
"We must press on to new heights and we must also recognise that we gather at a time of unprecedented challenges for Northern Ireland, combined with uncertainty within these islands, across Europe and around the globe.
"There is no escaping from Brexit."
The conference is one of the best-attended in the party's 50-year history with almost 400 delegates at the Stormont Hotel.
A range of young representatives, most of them first time councillors, addressed the gathering.
Additional reporting Tommie Gorman