Around 6% of pupils are now taught together in Northern Ireland, around 20,000 young people, meaning that they are still the exception to the rule.
But despite some opposition the sector has grown in recent years.
The first integrated school was Lagan College, which started with just 28 pupils when it opened 30 years ago in 1981.
Today, teachers at Hazelwood integrated primary school in north Belfast - strategically placed on the peace line straddling two divided communities - believe the impact of integrated education reaches further than the classroom.
Principal Patricia Murtagh said: "The type of integration we do is a different type of integration in that it's not really always about Protestant and Catholic, it's much wider.
"So we encourage our children to talk to eachother in spite of whatever differences they have."
Every year around 1,000 pupils miss out on a place at their preferred integrated school.
The cross-community Alliance party said it wants to see at least one in every five children taught that way by 2020.
The integrated education fund provides independent support to fledgling schools.
It says if a target similar to Alliance's proposed 20% model is set, it will be met.
"I think the goals are realistic if the Department of Education becomes proactive to support integrated education," Tina Merron told UTV.
"We are aware that the department has a duty to encourage and facilitate but it is not proactive in that duty - if there was a target of 20% by 2012 we think that could be met."
Meanwhile the Catholic Church maintains that it supports integrating education, rather than endorsing the prescribed integrated formula.
Bishop David McKeown said: "If the call is to move towards the integration of education we are fully behind that. Catholic education is as happy to be a partner as anybody else.
"If the Alliance Party is saying there's only one form or possible way that can be said as contributing, then I think all the evidence suggests that is wide of the mark.
"There are lots of schools that are not formally integrated but are much more integrated than schools that are formally integrated."
Sean Rodgers MLA of the SDLP was critical of the Alliance proposal.
He said: "It is clear that the Alliance party see no role whatsoever for faith based education and this is a fundamental flaw in their proposals.
"Their claim that the integrated sector has huge support across the community is simply not true. The reality is we should be working to ensure a diverse range of schools are supported and impart an enriching educational experience on our young people."
There are now 62 integrated schools across the region, but as work continues to promote shared learning, the presence of physical barriers such as peace lines serve to illustrate the challenges that still face the sector in some of the most deeply divided communities.