This isn't strictly a brewing book but I thought it would be good to have a review because I found it quite handy. I've wanted to look into this subject since trying a very old bottle of Fuller's Vintage Ale which completely blew my socks off. It's a guide to which types of beers benefit from age and it goes into the science behind this for different styles so you can have an idea of what to expect. The book touches on the types of recipes and ingredients that'll age well and how the different flavours will react. I can see myself using quite a bit of this when putting recipes together. Some of the flavours described when aging beer are the same as the off flavours when making it and that's handy for brewers. It's a fairly small book but well put together. It's by an American author so there's a fair bit about their beers but plenty about UK and European beers too. A decent read.