Recently I have been doing a lot of work looking at topology during my little quest to make a decent model of a person. The head has been of particular difficulty to me, as it is such a hard thing to model. I have recently been able to get back onto my escape studios lessons for a little bit of help on the matter. Half the difficulty with modelling a head is getting the topology right or finding a good topology for you, this means making the right edge loops to best describe the face, and in the case of animators deform in the best way to allow you to make realistic looking animations. These screenshots are from a tutorial I have been doing which suggests a good topology, in the images I have constructed all the edge loops I need (and have all the specific points in place that all that remains to do is simple bridging and appending the polygons) this head was made by making live a hi-res 3D reference and using the cv curve tool and the loft surgace to create the edge loops. This is not my ideal work flow as it requires you to have either a 3D scan of a head (I dont have a 3D scanner) or have a hi resolution mesh (ie from zbrush) well if I could make a hi res mesh in zbrush I doubt I would have any trouble making one in maya. But that aside it has pointed out a good topology to work with, so the next challenge will be to make this topology from a box model.