With three dogs going on a walk takes alot of planning.  three leashes and yes alot of poop bags.  With these bags, you can use your hand inside two layers of plasic, pick up the mess, and just fold the long white part over with plenty of lenth to tie a knot.  The plastic also feels heaver that most of the other bags, maybe 3 times as heavy as a grocery bag.  And since we care about the enviorment, being biodegradable is important.  We first encounted them at a dog park and if they were good enough for them, they were good enough for us :-)