The Work Style Reform Law and associated revisions to labour law have come into effect since this April 1st. The comprehensive package of reform and revision in the law consists of 3 main pillars. The first is a legal cap on overtime working hours. The second is the implementation of “equal pay for equal work” in order to eliminate unreasonable wage gaps between regular and non-regular employees. . The last pillar is “enhancement of flexible working time management, including extension of settlement period for flexi-working time system from 1-month to 3-month, introduction of a “highly professional” work system, and a work-interval system. In particular, flexi-working time system has become very popular among foreign-affiliated companies due to improvement of work-life balance. Though the flexi-working time system may enhance motivation and productivity of employees, some companies fail to make the most of the positive side of the system; introducing the system even to back-office/administrative divisions, not setting the important rules and not stipulating the provisions in rules of employment, and inefficiently generating long-working hour environment at work places. Prior to introducing the system, it is highly important to consider ①if the system is necessary to apply, ②to which departments and ③to which lines of work to apply the flexi-work system. On top of that, the following items must be required to determine as labour-management agreement: 1) scope of workers who are subject to the system, 2)the settlement period (if exceeds 1-month, must be submitted to LSIO, 3)the specified starting date of the month, 4)the designated working hours, 5)the standardized daily working hours, 6)the core time slots, and 7)the starting time and the ending time, which are subject to the decision-making by each employee. The above issues must be disseminated thoroughly among the employees whom the system will be applied to.