For the uninitiated (and aren't we all at one time or another), web services are programs that rely on SOAP (Simple Object Access Protocol) to expose their interfaces across the Internet. This means you can write a program and, if you make it a web service, you will expose its public interfaces for anyone to use via the Internet.

This book takes a normal O'Reilly tack of presenting in-depth information that is appropriate for users who want to know the wherefores behind the decisions. The authors present the Microsoft/Visual Studio methodology where many of the tedious tasks of Web Service development are performed for the user. They also do a solid job of presenting why that work must be done by someone and how to do it if you don't want to use Visual Studio .NET (VS.NET). The book gives good information (about 30 pages) covering Web Service Description Language (WSDL) before it covers the incredible facility VS.NET provides for generating these documents. WSDL docs are necessary for every web service you build if you expect anyone to use your program. The authors explain and lead the reader through the process of writing a web service and consuming a web service. They also expend effort on discussing stateful versus non-stateful web services and how to appropriately choose the best methodology for your application. With the performance gains that can be attained in IIS 6 via caching, the assertion the authors make about considering caching during design phase rather than after development is in testing or production struck a chord. The book covers IIS 6's caching choices as well as explaining the benefits and drawbacks of both. I didn't finish the debugging and security sections but plan to get back into the book and finish them as they look valuable.

In conclusion, if you want to mine a book for a robust understanding of web services and the constituent pieces of that technology (with all your examples in C#) then this book is for you. If you're looking to get a 5 minute read and start throwing code (and probably exceptions), pick up a less thorough book. You'll actually read this one instead of just looking for examples to copy. The information this book imparts should be standard knowledge for anyone that expects to write production quality web services.

This book is a reasonably compact and readable introduction to doing web services in the .net framework, covering everything from the basics of exporting an asmx page to doing transactions as part of a request, debugging and authentication, and other advanced details. I liked the bits on configuring asp.net, as I was never going to go through all the msdn docs to find what I needed.

I'm not going to give it five stars for the following reasons, reasons which make me worry about how much real world web service dev the authors do

1. it presents UDDI unquestioningly. This is tough. We all know UDDI outside the internet is bogus, but it has a place behind the firewall. This book looks at UDDI beyond the firewall like its a good idea.

2. It doesn't worry enough about soap interop. It has a chapter on it, but doesn't go into some of the glaring interop issues you can do in .net like use unsigned datatypes (breaks java), or DataSets (breaks everything but .net). Developers need to know these things if they want us java coders to talk to their service