This is a collection of Niven's stories of the bar where aliens get refreshment as alien starships pass by earth. The stories span 20 years, and I've read several of the older ones before, but there were a bunch of new ones that I hadn't seen before. Most of the individual stories are quite short and serve as vehicles for exploring single ideas of how aliens might be different from humans and how humans might deal with it. They're not big on character development individually, but they do fit together into a sort of narrative of the life of the proprietor of the tavern. I think they're excellent examples of what hard science fiction is supposed to be: create a setting that's definitely not the real world but believable enough that one can read it without checking one's brain at the door, and create a situation within that setting that prods the reader into thinking about some aspect of the human condition.
These stories are fun and thought-provoking. They aren't the finest poetic prose, but they don't need to be; in fact, it would get in the way. 9 out of 10.