HI, I am coming from Milkshape and a little from 3DS Max and my question is, is it possible to take a sketch of a character and model it in Houdini using the four viewports Left, Right, back, and top?

Yes,
select the 4 viewport layout and press ‘d’ in each viewport to set the background images

regards

erik

You might want to check this post out
http://www.3dbuzz.com/vbforum/showpost.php?p=1422679&postcount=3 [3dbuzz.com]