Japan's Parliament tightened limits on overtime hours, responding to concerns about karoshi, or death by overwork, and seeking to improve productivity in a country where long hours are often more a custom than business necessity.
The legislation, a priority of Prime Minister Shinzo Abe, won final approval last Friday in Parliament.
It limits overtime work to less than 100 hours a month and less than 720 hours a year, and it sets penalties for companies that violate the limits.
Until now, employers could effectively ask employees to work without limit if workers' unions and management agreed to it, which they often did without much scrutiny.
"Work-style reforms are the best means to improve labor productivity," Mr. Abe said in Parliament June 4. "We will correct long working hours and improve people's balance between work and life."
The new law also seeks to improve the lot of Japan's growing pool of "nonregular" workers in temporary or part-time jobs who don't have the job security of full-time regular employees.
It says employers must pay equally for the same work, regardless of workers' status. In a 2016 interview with The Wall Street Journal, Mr. Abe said he wanted to "eliminate the word 'nonregular' from the lexicon."