Harry Harrison is normally a funny writer so reading this book from him was a bit of a shock. It's not funny at all and rather depressing actually, the ending isn't all that happy and nothing has changed, society keeps plugging along on the same path to oblivion, people have lived and died and in the end it's all the same. No wonder why it was taken out of print. But by the same token, it'll be one of the best books you've ever read. For those who watch movies, the film Soylent Green was based on this but the main point of that movie doesn't even come into play here. If anything it's a love story disguised as a mystery story, showing how people still try to live and love with too many people crammed into too many creaking, cold and leaky apartment buildings, the measures the police have to do to survive along with everyone and it submerges you completely in this world that makes you glad that you can go outside and not have to withstand the crush of millions of people. One of the best books in this line of reasoning, a very similar and probably better examination of this (though not by much) would be Thomas Disch's 334 and for a wider look at the entire planet with too many people try John Brunner's Stand on Zanzibar. All three form some of the keystone books of thought on the matter of overpopulation in fiction and if you want to do even more exploring, look for The World Inside by Robert Silverberg, which I haven't read but I think deals with the same issues. Make room for it on your shelf today.