I've been using this guide for the last 3 summers. When it comes to an all-round UK insect book for the enthusiast your choice is pretty much limitedI've been using this guide for the last 3 summers. When it comes to an all-round UK insect book for the enthusiast your choice is pretty much limited to Michael Chinery's books (more on which later). There are several other books about but generally I've found them to be a bit more limited in scope and detail. The main problem with guides like this is what should be included in a pocket-sized guide to a group of animals ~24,000 species strong in the UK alone.
This book still fits into a large-ish pocket while covering about 1,500 species and including many of the most commonly encountered species in the process. It also covers some of the spectacular ones and tries to include at least one representative for the many families out there (once again, hard to do when Brit beetles are grouped into 100 families!). The book even covers a small selection of non-insect arthropods (eg. spiders) to help the beginner out.
In a very small amount of text per species, Chinery fits in a description with diagnostic features, very basic distribution map (represented by a triangle and a symbol), seasonality, food plants and sometimes notes on the larvae. I also appreciate that Chinery has often put the effort in to note when there are many very similar species that realistically need further reference material and a microscope to identify. Later on if you get even more into insects you'll appreciate these pointers.
The illustrations are great. The moth illustrations in particular are beautifully detailed. Extra illustration is sometimes provided for key features (eg. the pronotal keel markings on grasshoppers). Every illustration has a useful multiplier symbol next to it to indicate the size of the actual insect relative to the drawing.
One of my few gripes is that while it could never cover everything, there are some things it doesn't quite cover well enough. The most charismatic insects are generally the relative large or colourful ones - butterflies, moths, dragonflies, ladybirds, bumblebees, crickets and grasshoppers. Of these he really fails to cover the butterflies or ladybirds very well. But these are exactly the kinds of groups that people start out on. For a few extra pages or a dozen fewer of the more specialist species, he could have more comprehensively covered the kinds of insects that make the amateur reach for the ID book.
That said, I frequently refer to it in the field with groups I'm unfamiliar with and have often been surprised when it comes out trumps on stuff like mirid bugs or tachinid flies.
It's worth quickly comparing this book to Chinery's other very similar books:
Complete British Insects This is largely photographic and appears to cover mostly the same species. In my opinion, photos can often miss the important features that need illustrating on some species.
Collins Field Guide: Insects of Britain and Northern Europe This appears to be another excellent guide. Slightly different geographical focus. The editions I've seen have been a bit too big and heavy for a fieldguide. On the other hand it does have very nifty keys to the families of most of the insect groups.
Overall a fantastic book and one that rarely sits on the shelf in summer as it's so often in my rucksack or pocket.
2014 edit: Since I wrote this review, Paul Brock has put together a Britain and Ireland-wide version of his excellent New Forest field guide: A Comprehensive Guide to Insects of Britain and Ireland. I've only taken it out with me the once so far but I'm already really impressed with it. I'll put up a review of it later in the year after a few more outings....more