I feel that this book is very good at introducing the concepts of the Microsoft Distributed Network Architecture (DNA) and taking the understanding of these concepts to an intermediate level. The introduction suggests that there are three main groups that would benefit from reading this book; the Visual Basic hobbyist turned professional, the Visual Basic professional moving to distributed applications and the advanced Visual Basic professional. I would say that those who know very little about COM/DCOM would get the most out of this book. I think that this book is aimed at the beginner to intermediate level and advanced programmers would get little from it.

My first thought when I picked up this book and flicked through the pages was 'Yes, it seems to cover all of the basics'. This it does, but I was a little disillusioned after finishing the book. In my opinion the book, while claiming to teach 'all about' building NT application with COM and Visual Basic 6 , it does not tell all needed to know to build N-Tier applications with Visual Basic 6. The book covers COM, DCOM and MTS with two chapters each. One chapter is an introduction. The second of the chapters is more in depth. The introductory chapters explain each of the technologies, how it fits into the N-Tier picture and how you can use the Visual Basic wizards to help create components. The second group of chapters go into some of the details that you don't need to know as a VB programmer, for example the IUnknown and IDispatch interfaces, marshalling and proxies and stubs.

The other chapters cover concepts such as thin clients, the web browser as a client and business rules.

The last chapter is titled 'Putting It Together'. This chapter contains an example of buying a pet from the web. It leads you through all of the steps of design and implementation giving all the code required.

The accompanying CD contains a number of Visual Basic projects for each of the chapters. These projects contain all of the source code mentioned in the book. The CD also contains a number of demo versions of related software.

The book is very conceptual yet written in a very easy to read style, with practical examples, which would help the reader to understand the concepts.

This book is recommended but only as a beginner to intermediate introduction to COM and distributed applications.