The email was unambiguous: "As opponent, your role is to summarise the dissertation, interrogate the candidate I and then sum up the strengths and weaknesses."
The invitation might have added, "Iin public, in the university amphitheatre and in front of up to 200 of the candidate's relatives, friends and colleagues, three learned judges - who will decide the fate of the student - and anyone else with a couple of hours to kill on a grey morning in Stockholm". And I would be paid £500, which was a little more than I was used to in England.
The process goes something like this: first, the opponent makes a brief summary of the dissertation, then, for an hour or so, a dialogue ensues between the opponent and the candidate, after which any of the judges and members of the audience can ask questions or make a statement. The public event is then concluded and the judges, opponent and supervisor retire to deliberate and produce a result - that is, a pass or fail.
At the appointed hour, I squeezed through the throng of supporters (hers, not mine) to take my chair behind a modern Ikea-style desk carefully positioned opposite the candidate.
Hoping for at least Swedish neutrality from the audience, I began my opposition with a smorgasbord of questions: a raw opener here, something lightly grilled there, and perhaps a just dessert towards the end. For the most part, the onlookers behaved with a judicious blend of Swedish formality and personal warmth, with beaming smiles, supportive laughter and a detectable appreciation of my efforts to both examine the thesis and allow the researcher the opportunity to publicly reward their faith in her.
Once I had summed up, the judges each asked a question, somebody at the back asked something and then we were quickly ushered into a quiet "jury" room to deliberate her fate over a splendid lunch of open sandwiches and cold bottles of Swedish beer.
As a pass became the obvious, and deserved, outcome, I was told that the candidate is alerted to any likelihood of failure way before the day and a postponement sought. And, considering the planning that had gone into the evening celebrations - in the grounds of a castle owned by the university - I could see the wisdom in this.
For the candidate, she had had an opportunity publicly to defend and display the fruits of her labours before her teachers and those who had supported her over five years of study. And for the examiners there was no opportunity to intimidate or dismiss the candidate's work behind closed doors.
Is a public grilling not a fairer, more accountable way in which to examine a PhD student than a private roasting behind closed doors?