Having a thick, wide back is the cornerstone of any quality physique.  It can make you look full, powerful, and improve your posture.  It also gives you that sought after v-taper making your shoulders look wide and giving the appearance of a much thinner waist.  Building a wider back is relatively easy provided you have the right exercises, the right techniques, and the ability to push yourself to your physical limits and beyond. 

Any type of pulling movement, that is, pulling your arms closer to your body whether it be in the form of a row, or in the form of a pull-up/pull-down is working the back muscles.  Their responsible for retracting the upper arm to the torso - all of these movements involve this action.  With this in mind we then can construct a workout routine that hits all the angles of the back providing optimum stimulation and thus muscle growth. 

The back is a muscle that often responds to heavy weight and low reps.  While I know everyone is different when it comes to adding muscle to their frame, I've noticed throughout the years that most individuals respond best to heavy and intense training - no wimps here.  There are two main movements for the back - the pull-down and the row.  The pull-down movement really focuses on the outer part of the lats(depending on your grip of course) and gives the appearance of a wide back when looking at someone from the front - it also can really add shape to your v-taper.    There are many different versions of the pull-down; close grip, wide grip, reverse grip, pull-ups, and myriad of others that add variety and thus new stimulus.  It's extremely important to work all angles for maximum muscle stimulation.   

The send big exercise for the back is the row.  There isn't a better exercise for putting sheer muscle on your back than this one.  The row incorporates nearly every muscle and allows for the most weight to be used.  It stimulates the most muscle fibers and thus stimulates the most growth.  The most important thing to remember when performing the row is to keep your back strait and tight, never let it round at all.  If you do let your back round you put it at extreme risk for injury, along with that it takes the tension of the exercise off the muscle and places it on the spine - not something you want to do.  So keep your back strait and your body upright.  The key to effective rowing is pulling your hands towards your body in a way that it causes your shoulder blades to come together.  It's this movement that really important.  You'll see a lot of guys doing the row but are using most arms and delts for the movement.  Don't let this happen to you.  Stick out your chest, bow your back, and let your back muscles do most of the movement.  It requires some degree of focus to do the movement right, but once you get it down you'll see muscle growth like never before.  There are various grips, bars, and movements of this exercise that can produce new stimulus and get the back growing again.  So switch things up every now and then. 

These two movements are the cornerstone of any successful back routine.  Minor variations in the way you perform can equal to big gains in the gym, so be sure to switch up your grips, the weight, the amount of repetitions, etc - change equals growth.   Provided you have good form, good technique, and have the ability to focus and let the muscle do the work rather than momentum your back should begin to grow to proportions otherwise thought unachievable.