It was introduced by Canon on 8/22/2005. I reviewed it back on 4/19/2007. I compared it with the EF 24-70mm f/2.8L lens back on 10/5/2007 and deemed it superior. I complained that I didn’t have it on 9/14/2008, after coming back from our trip to Austria. Now I finally bought it, and I am not sorry. At long last, I have a versatile zoom I can use just about anywhere. I am giddy with joy.