I personally don't recommend the "Essential COM" book for beginners. Wait until you've had time to read and absorb other books and on-line documentation. If you wanted to develop a COM object from scratch in C or C++ w/o using ATL (3.0 or 7.x), then that book would still be my second/third choice. I actually bought a used copy since I thought it would be useful to debug some tough problems (like apartment threading models and memory allocations) and to describe the architecture and fundamentals of COM programming. The book didn't help much and I debugged the problem by reading a lot of MSDN documentation and then calling Microsoft tech support (MSDN incident). Now that I have the "Essential COM" book, I rarely use it as a reference since I use ATL so extensively. If you're like me, I like to have a solid understanding of the fundamentals so the "Developers Workshop" book is a good choice. But with ATL, most of the COM 'plumbing' details are taken care of (and you have all of the source code in .h and .inl files). What tools are you using? Visual Studio/C++ 6.0 or .NET? If you're using .NET, I can send you a few tips to help with your learning curve. Jerry

Here are the books that I use: For COM beginners: "Developer's Workshop to COM and ATL 3.0" (first choice, learn COM fundamentals) "The COM and COM+ Programming Primer" (second choice, has COM+ stuff too) For experienced COM programmers: "Essential COM" by Don Box (a.k.a. COM bible, seems dated now, no ATL stuff) "Effective COM" (some useful tips, not for beginners) Although there are no good books for ATL 7.x, I highly recommend using Visual Studio .NET 2003 (with ATL 7.1) so you can take advantage of attributed programming and all of the great wizards. If you're going to use connection points, there are some attributes ([event_source], [event_receiver]) that make it very easy to implement. If you're new to C++ attributes, the learning curve is worth it. Good luck, Jerry