So many times have I read through workout programs people post on this site, and so many times i notice the same thing- Little to No Hamstring work.
The Hamstrings are the Biceps of the leg, and in coordination with the Glutes, provide a great deal of power when squatting, not to mention the fantastic visual appeal of well worked hamstrings.
I post this for all those who are simply hitting the tip of the iceberg when it comes to hamstrings. I personally know a man who has blown out his quads due to overstimulated quad work and growth and little hamstring work, and i fear it is very well a possibility for some.
Take the hamstrings more seriously, for your benefit. I personally do just as much hamstring isolation as i do for the quads.
Some options, aside from squats, include deep lunges, Romanian Deadlifts, Glute-ham raises, etc.