Did you know that hairbrushes need a shampoo once in a while? When I see my hair brushes getting grungy I know it's time. So when I noticed there was a layer of hair and some dust I did what I needed to do. I gathered up my hair brushes and put them in some warm water and added some of my shampoo. I let them sit for a minute or two and then grabbed a comb and began to remove the hair from the brushes. I find the hair is more manageable when wet. I threw it all away, of course. Then if the brush seemed dirty in the center I used another brush to clean it by scrubbing the other brush against it. Next, I emptied the sink. You will find that your brushes might catch dirt as well. So I refilled the sink and rewashed slightly and rinsed. Then I put my almost back to new brushes to air dry. Quite happy with the results.