Overall, I think there is a need for this library and it works as described, so it should be Accepted. However, I have a serious concern with the performance when generating large numbers of GUIDs (see below). If not addressed, this might cause people to choose faster solutions over this library. - What is your evaluation of the design? I think the design is reasonable and complete enough for my use. I agree with a previous comment that UUID would be a better name for the library. - What is your evaluation of the implementation? I am concerned about the performance of this library when generating a large number of GUIDs. I wrote two small programs to compare performance between MSVC 8.0 native mode using the Boost.GUID library and C++.CLR using the Microsoft System.Guid library. The CLR version ran much faster. For ten million GUIDs, the times were 5 seconds for System.Guid, 16 seconds for Boost.GUID (random number based) and 12 seconds for Boost.Guid (name-based). The source code for the programs is attached. I would have expected the native mode program to run faster or about the same. Is there something wrong with my code? Could this be caused by the Thread lock? Or maybe the random number generator takes more time? - What is your evaluation of the documentation? At the start of the document, I would prefer a text paragraph or two describing what a GUID is, what they look like, and what the library does with them (input/output/create). Also, a description of the name-based and random-number-based alternatives might help up front. In the Design Notes section, could you provide a link to a SHA-1 reference like http://www.itl.nist.gov/fipspubs/fip180-1.htm. - What is your evaluation of the potential usefulness of the library? I think this is a useful library for many purposes. With multi-threading and multi-processor architectures becoming more popular, UUIDs will be used more frequently. - Did you try to use the library? With what compiler? Did you have any problems? Yes, I tried a minimal example to test the performance using the MSVC 8.0 compiler. See my performance concerns above. - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? Moderate. I read the documentation and skimmed through the source code. - Are you knowledgeable about the problem domain? I have used UUIDs in the past and know, in theory, how they are generated. But I have always used databases, libraries, or utility programs to generate them. Regards, Dave Jenkins