Most Israelis are drafted into the military at the age of 18. Men serve two years and eight months and women two years. Following mandatory service, Israeli men join the reserve forces and usually do up to several weeks of reserve duty every year until their forties. Most women are exempt from reserve duty. Arab citizens of Israel (except the Druze) and those engaged in full-time religious studies are exempt from military service, although the exemption of yeshiva students has been a source of contention in Israeli society for many years. An alternative for those who receive exemptions on various grounds is Sherut Leumi, or national service, which involves a program of service in hospitals, schools and other social welfare frameworks. As a result of its conscription program, the IDF maintains approximately 176,500 active troops and an additional 445,000 reservists.