Edit model from within Sheet/viewport

Hi - giving swym a try - new computer, 64bit, Acad2006 won't work so moving to DS, looks familiar enough - but several questions, which I'll post separately.

 

In Acad2006 I could enter Model mode and edit, without leaving Paperspace/viewport. Can DS do that, or can the Model tab only dump me back to 'anywhere' in Modelspace?