This isn't my full review, just a few issues I see. I think this library has great potential and value, but I'm going to stick to the issues for now. I posted most of this just before the review, but got no response: http://lists.boost.org/Archives/boost/2006/04/103305.php I see 3 serious issues at this point: 1) Find is under documented / doesn't work for me ptree pt; read_ini("test.ini", pt); ptree::const_iterator ci = pt.find("value2"); if (ci != pt.end()) { std::cout << ci->second.data() << std::endl; } //test.ini [User Data] ; This is a comment value1 = v1 value2 = v2 date = 2006-Apr-18 I tried various keys in the find including: ptree::const_iterator ci = pt.find("User Data.value2"); All returned null iterator. So there are two problems. From the docs it wasn't clear what syntax to use with find and it doesn't appear to work. 2) Iterators are underspecified It was totally unclear to me from the docs what the interface to iterators returned from the interface. I finally found a test or example and copied. std::cout << ci->second.data() << std::endl; 3) Write operations are not 'whitespace' and comment preserving To me this is a critical point not fulfilled by the library. Most real-world configuration files have comments. If the application needs to read/write the files it needs to maintain the comments as human written. In my experiment if I start with this: //test.ini [User Data] ; This is a comment value1 = v1 value2 = v2 date = 2006-Apr-18 After I write it back I get: [User Data] value1=v1 value2=v2 date=2006-Apr-18 I realize that this requirement might increase the resource usage of property_tree, so I'm fine with this being an optionally enabled feature. Jeff