UUP leader Mike Nesbitt has admitted to a "very difficult" first year in office.
But following a stream of departures from the party, he said he was starting year two with "expectation and a huge sense of opportunity".
Addressing the party's AGM, Mr Nesbitt also expanded on controversial comments he made last week when he declared that the UUP should learn to "apologise" for the Good Friday Agreement.
Those comments were attacked by high-profile UUP quitters, John McCallister and Basil McCrea, who plan to set up their own party.
Mr Nesbitt said the values which had underpinned the party's support for the 1998 deal had been fairness, consensual politics and mutual respect.
At the gathering on Saturday, he added: "As we approach the 15th anniversary of that agreement, it is time to face up to the massive failures in implementation.
"We all need to refocus on delivering what we had in mind back then. That is a massive challenge given how differently the main parties see things."
In his keynote speech, Mr Nesbitt called for an agreed definition of 'reconciliation'. Mr Nesbitt said he suspected the five Executive parties – DUP, Sinn Fein, SDLP, Alliance as well as the UUP – have five different interpretations of what it means.
He said if parties could agree, "it will bring great comfort to victims who fear Sinn Fein's definition of reconciliation means having to hug the person who hurt you, or murdered your loved one".
An audience of several hundred at the King's Hall in Belfast heard Mr Nesbitt attack Sinn Fein.
He argued that the republican party is only opposed to majority rule when it is in a minority, pointing to the Union flag decision at Belfast City Hall which led to months of violent protest and the setting up of the Unionist Forum.
"As soon as they sensed the opportunity for majority rule in Belfast, (Sinn Fein) abandoned all pretence of being a party of consensus – and seized the chance for an unnecessary and divisive vote – which not one unionist supported," he said.
The UUP leader also insisted there are major differences between his party and the DUP. When the UUP supported the 1998 agreement it had put country first and party second but when the DUP "finally came on board" in the St Andrews Agreement they had put party first with "six long years of consequences" for the economy, health service, education and housing.
Mr Nesbitt appealed to the other Executive parties to allow the UUP to take over education, if the Department of Employment and Learning is scrapped and the d'Hondt procedure for sharing out departments is rerun.
He said while there are problems in the grammar sector which remains too big, the real problem is the huge number of pupils leaving school without decent basic skills in literacy and numeracy and teachers who are "not being allowed to teach".
He concluded: "I am well over 50 years of age. I have never lived in a Northern Ireland at ease with itself, with its citizens comfortable in their own skins, prosperous, healthy, with a positive sense of purpose in their lives.
"That's my vision. It could lead to a day when people vote for what they hope for, not because of what they are afraid of."
Earlier, former leader Sir Reg Empey sounded a stern warning that the party will push its own agenda – and that devolution at Stormont would not exist if it had not taken hard decisions in the past.