How do you rate the success of a state visit? There are three essential criteria from which to assess it: organisation, execution and perception.
When Kensington Palace announced last month that the Duke and Duchess of Cambridge would be visiting Ireland for the first time, the royal couple said they hoped to "build a long-lasting friendship with the Irish people".
Diligent organisation is key for a trip of this magnitude to work, factoring in the near-constant security threats, anticipating inevitable criticism and balancing personal causes with compulsory diplomatic niceties.
Their itinerary was planned roughly three months ago and, soon after, palace representatives began to reach out to community outreach programmes, balanced with the obligatory tourist attractions.
Their visit to Jigsaw, a youth mental health charity with its headquarters in Temple Bar, was set up by the Cambridges, both of whom have adopted mental health as their professional raison d'être.
Similarly, a visit to Extern, a social justice charity which works with vulnerable families in Prosperous, Co Kildare, not only reflected the level of research that went into planning their trip, but the commitment to their advocacy.
Sources told the Irish Independent the couple requested a private meeting with service users and staff to understand their work at a grassroots level, breaking protocol with a lengthy - and discreet - discussion about their work.
It was essential to both sides that this trip went well, or at least the perception of it. The British royal family is in crisis and its future stability seems to have fallen solely on Kate and William's shoulders.
At 93, Queen Elizabeth no longer carries out international engagements, her husband Prince Philip retired in 2017, Prince Andrew resigned from public life in disgrace after his friendship with sex offender Jeffrey Epstein, and Meghan Markle and Prince Harry have left their roles as senior royals with the goal of eventually becoming private citizens with financial independence.
The Department of Foreign Affairs knew what was at stake as both sides commit toward a future of more stable Anglo-Irish relations.
"The changing relationship between the UK and the EU will require us to work together, to ensure that the relationship between Ireland and the UK remains just as strong," Prince William said in a speech at the Museum of Literature of Ireland, hosted by Tánaiste Simon Coveney.
"I am confident that friendship, understanding and a shared vision for a peaceful and prosperous future will ensure that the unique and precious bond between our people is not broken. My family is determined to continue playing our part in protecting, preserving and strengthening that bond."
It was the closest thing to political commentary we've heard from a British royal.
William spoke about memories of the Troubles as a child, the significance of visiting the Garden of Remembrance, and "the complexity of our shared history".
If this visit was about ensuring the endurance of the British monarchy, it was just as important for Ireland to show it's "business as usual" with our neighbours after Brexit presents its own economic uncertainties here.
Such high-profile visits also allow Ireland to be shown on the global stage, highlighting myriad tourist attractions, including the Howth Cliff Walk and shining a light on Galway's colourful offerings.