Simple Emboss - Add vertices to a face? I want to add a simple 'pillow' emboss shape to a face. I want the shape to be square with rounded edges and lift off the face a couple of mm. It needs to be part of the face with seamless joins as if it were punched out of metal. I've attached my efforts so far but as you can see the subsurf is doing some funny things to the straight lines. Is there an easy way to add a square face within a face that I can then extrude?
I hope I understand what you need. 
If you are doing square indentations you will usually need to use a grid topology to not get artefacts with the subdivision modifier. This will keep the edge flow align to the edges instead of creating a circular edge flow. Add at least one extra support edge to get flat surfaces around the indentation.

(You should also use smooth faces so you wont get small facetts.)