Last year it was estimated about 40,000 people took part in one way or another, and the spread of nationalities was as remarkable as the spread of spats, hats, canes, scarves, wraps, frocks and braces.
One of the most heartening comments I heard during last year's festival came from one of the sons of Dilmah founder and Deco ambassador Merrill J Fernando, who had arrived in the Bay's own Brigadoon to take it all in.
"How do you do this?" he simply said as the soapbox derby was on the roll, as a couple of old bi-planes soared overhead, as steam engines chugged and burbled nearby, as people of all ages dressed in attire of the 1920s and 30s laughed and lounged.
It was, he said, the most memorable event he had ever attended anywhere in the world — and he'd been to a few.
Not surprisingly the Fernando folk are back again, which is great.
They, of course, will be joined by about 40,000 others.
As the event bookings show, there are a good number of Australian folk who dust off the dashing duds to take part in a once-a-year holiday with an unbeatable difference.
And they come from as far afield as Europe and the United States and, as it has been in the past, on the Monday when Brigadoon dissolves back to 2016 they will book more than just flights home — they will book flights and accommodation for 2017.
For the people, it is special. For the economy, it is golden.
What-ho, and here we go.