SSD (Society System Decontrol) was a straight edge hardcore punk band from Boston. They released two records as SS Decontrol and then formally changed their name to SSD. As SSD they released two more records, these with a very heavy metal influenced sound. However the group is often simply referred to, including all its periods, as SSD. Formed by songwriter/guitarist Al Barile (then a machinist at the General Electric plant in Lynn, Massachusetts and a student at Northeastern University)