Pretty much all the well-known and best-loved shorter Vance stuff is here in this single collection. There are the Hugo-winning novellas The Last Castle and The Dragon Masters, the short stories The Moon Moth and The Kokod Warriors, Sail 25, and others. There are a number of "extracts" from the Dying Earth series - including Liane the Wayfarer and some Cugel the Clever (in fact, there is multiple Cugel).
Generally, this is "mid-period" Vance: already a skilled artisan, and rapidly becoming a master. The unique Vancian voice is in full flow, and yet there is enough structure and plot to each story that each is substantially different. What we are generally looking at is a dissection of an alien culture, social satire set in a future world or a fantasy past, usually with an irrepressable hero - or at least, protagonist.
I'd read some of this stuff already, but most of this was new to me: if you can stand short stories, this is a nice introduction to Jack Vance. If you cant stand short stories, then Lyonesse is probably the best way to see if Vance is for you.
This is a wonderful collection of beautiful tales, that you can read just for the joy of it, but will repay tenfold a little thought and engagement.