The Republic's Foreign Minister, Charlie Flanagan, says the Fresh Start document gives grounds for optimism, but without the legacy institutions envisaged in the Stormont House Agreement we risk the toxins of the past poisoning the politics of the present.
The year 2015 was another politically turbulent one in Northern Ireland that involved the presence of the Irish Government for an intensive talks period over two-and-a-half months in the autumn.
I was very pleased, however, to see out the year with the conclusion of the Fresh Start agreement - yet another milestone in Northern Ireland's journey towards long-term peace and stability.
During the autumn talks process I hosted an event in Dublin to mark the 30th anniversary of the Anglo-Irish Agreement. This event brought into sharp focus just how much has been achieved in Northern Ireland over the past three decades; it reminded me why this peace process is so important and strengthened my resolve to see a successful conclusion to this latest round of talks in the form of the Fresh Start agreement.
Since my appointment as Minister for Foreign Affairs and Trade in July 2014, with a strong mandate from the Taoiseach, I have made Northern Ireland a priority - for me personally and for my department.
On my first day in office I telephoned Secretary of State Theresa Villiers to discuss our roles as co-guarantors of the Good Friday Agreement and how we could best work together to realise the full promise and potential of that transformational document.
I know that many people feel frustrated by what must seem like the neverending crises in Northern Ireland politics. However, in spite of occasional moments of shrill rhetoric and interludes of sterile impasse, the overall trajectory remains one of progress towards stable politics and a peaceful society.
In fact, implementation of many aspects of the Stormont House and Fresh Start agreements has already begun, with a firm timetable in place for dealing with many of the other important and challenging issues - including bringing an end to the toxic legacy of paramilitarism.
The Fresh Start agreement represents a major step towards normalising politics in Northern Ireland. Failure in these talks may well have precipitated the collapse of the devolved institutions; it is to the great credit of the Northern Ireland parties that they were determined to succeed and to avoid that calamity.
They fully understand that the people of Northern Ireland want a functioning power-sharing government that delivers effective services for its citizens.
Therefore, while the tree of politics may bend, it has yet to break. There is a firm resolve among all those engaged in the autumn talks, myself included, to build a peaceful, reconciled, prosperous Northern Ireland that its people deserve.
This means taking a firm stance against the remaining pernicious influence and legacy of paramilitarism, while ensuring the success of devolved government that operates on the basis of partnership, inclusion and equality.
The Anglo-Irish Agreement of 1985 formally recognised the right of the Irish Government to put forward views and proposals in regard to the governance of Northern Ireland.
This was transcended by the Good Friday Agreement of 1998, which provided an institutional basis to properly reflect the totality of relationships across these islands.
The Irish Government takes its role as a co-guarantor of the Good Friday Agreement very seriously and I feel privileged to have represented the government in the various talks that have taken place during the course of the last 18 months.
We all prosper when Northern Ireland prospers. The stability of the devolved institutions in Northern Ireland is important for the success of the island of Ireland.
A stable government in Belfast is key to building a strong local economy and will contribute significantly to the prosperity of the island as a whole.
I truly believe that all the people on this island - and especially those living in the border region - benefit when we work together to advance north-south economic and social co-operation.
By working together on a small island, we can make the best use of its finite resources for the benefit of the greatest number of our citizens.
The Irish Government is committed to working with the Northern Ireland Executive to make this happen. We have committed €110m (£80m) under the Fresh Start agreement to cross-border projects that will help create jobs and unlock the full potential of the island economy.
This work of building peace, reconciliation and good neighbourly relations is not always easy.
There are many problems still to be resolved, but - considering where we were in 1985 - we are in a stronger position than ever before to successfully overcome the remaining challenges.
While I enter 2016 in a hopeful mood, I am also very conscious of the work that still needs to be done.
We must not lose sight of what, regrettably, was not achieved in 2015 - namely, the establishment of the legacy institutions envisaged in the Stormont House Agreement.
I am determined that agreement will be reached on these outstanding sensitive issues, but it will take commitment, courage and flexibility from the governments, the political parties and civil society if we are to find a way through this apparent zero-sum impasse.
Nevertheless, it is imperative that a solution be found. We owe it to the victims and survivors and we owe it to ourselves, since we cannot risk the toxins of the past poisoning the politics of the present.
So, taking heart from what has been achieved on the journey over the last 30 years, let us resolve in the centenary of the Easter Rising and the Somme to agree a way of dealing with the past so that it contributes to peace and reconciliation on the island we all share and we all cherish.
Charlie Flanagan is the Republic's Minister for Foreign Affairs and Trade