No. Not necessarily. I found this wonderfully helpful article about how to handwash cashmere, silk and other things most people dry clean. Read through everything on the page, especially the “Golden Rules” and take it step by step. I washed a cashmere scarf as well as a silk night mask (yes, I sleep with a night mask), and followed the directions carefully, and they came out perfect. One thing, however, I was not able to find the Lux or Ivory brand soap flakes the article recommends. So, I grated up the plainest soap I have (the very highly recommended True soap). I grated it up a tiny amount (that was just enough) with the very highly recommended Microplane and the rest, as we say, is handwashing history.
Do I have to dry clean cashmere?