A wave of informality is due to sweep through Japan with a government campaign to persuade office workers to abandon their jackets and ties. Offices are being asked to cut back on air conditioning this summer.
Temperatures and humidity rise to unbearable levels over the next three months in Japan's cities and so does the use of air conditioning.
The government thinks this is standing in the way of lowering its emissions of greenhouse gases.
So it has launched a campaign to get the country's salary-men to abandon their suits this summer.
Already some very strange sights have been spotted recently in Japan: a cabinet minister has been seen wearing a violently-coloured Hawaiian shirt and top business executives have been modelling casual wear on the catwalk. Sweltering
At the moment Japan is well behind its agreed target under the Kyoto Protocol.
So it has asked businesses to raise the temperature in their offices to a sweaty 28 degrees, making the standard jacket and tie uncomfortably hot.
However many office workers say they would feel even more uncomfortable without the formality and anonymity of suits.
So, it has been left to the politicians and bosses to set a new trend - calling it "cool biz".
From this month, cabinet ministers are expected to embrace a slightly more casual look, wearing shirts designed with studs and pins to keep the collars suitably stiff.
Members of Parliament have been told they too can dispense with jackets and ties in most sessions.
But there is a discouraging precedent for this initiative - in 1994 then Prime Minister Tsutomu Hata donned what he called an energy-saving suit, a conventional jacket with the sleeves cut off at the elbow.
Few people followed his example, and his administration lasted just 64 days.
By Jonathan Head
BBC News, Tokyo BBC News