Saab 5-Sep is a Swedish five-day working week system. It was introduced in 1993 and is based on a five-day working week with a two-day weekend. The traditional eight-hour workday is divided into five four-hour workdays spanning either Monday-Friday or Tuesday-Saturday. The weekend is usually a three-day span, with a rest day either on Saturday or Sunday. The system is designed to increase productivity, reduce fatigue and stress, and provide more free time for employees.