I think there are a few things. One, what they are made from. Two, how well constructed they are to hold their shape. And three, how they are lined, which will impact the kind and amount of light you get.

And then of course all of the little details and doodads.

The best lamp shades I've ever used are those from Lake Shore Studios. their catalog provides some explanations as well.

Here is a link that might be useful: Lake shore shades

Thank you and especially thanks for the link. I needed that! It will take me some time to figure this out. This is my bedroom, the swing arm wall lamps are antique brass (needed to man up the room a bit). On the other side of the room in the corner is a non-descript floor lamp, a chair and soon a small reading table. I need to replace the shade on the floor lamp; itâÂÂs disgraceful and has a dent. The room is a bit of a mix like the rest of the house. IâÂÂm partial to drum shades but IâÂÂm not sure if that will fly in here, need to tie in the headboard, wall mount lighting and the rest as best as possible. DonâÂÂt want anything to frilly or bell-y. I know I want a cream colored shade with some trim of some sort.
IâÂÂm stuck on a shape! I think I need a nice shade to counter some of the used stuff and make it all look on purpose.

Shade shape for this room???

If you have the lamp already, then the most important thing is that the shade go with the lamp.

I always take the lamp to the shade store and try them on ...it's the only way to know what the lamp really needs.

What Annie said - you really need to take the lamp to the store and try on several. Look at them with the light on too, as the color changes, and you'll see any texture in the fabric.

Most of our lamps are vintage or one-of-a-kind that my local lamp store owner has made, or I have taken something to her to make into a lamp. For me, picking out just the right shade is as much fun as finding the neat lamp base/having something made.

Nice shades can be expensive, especially when compared to Target or HomeGoods, but they last for years and really make a difference.

Ok Allison you canâÂÂt go around saying that that you have one of a kind lamps or things made into a lamp without showing me pictures, I love that kind of stuff.
As for the lamp shade fit/style I was just going to do the same size-ish thatâÂÂs on there already except maybe a different shape. Shows you what I know.
I did get off on a side track as usual this morning and looked on craigslist, there are some very cool vintage lamps way down south. Perhaps I need to look around a little before I decide on a shade for the floor lamp. A vintage brass would also look nice on the long dresser near the chair.
Allison, inspire me please!