Well i understand that one way is to use the size widget in the bottom left. I have aPhotoshop and i can easily change the brush size by using a keyboard shortcut, but i can't seem to find a similar method in art rage. Surely something as basic as this has not been overlooked. I have to say that having purchased this some years ago and only just found it after a move of home, i am totally amazed at the excellence of art rage.