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Tesseract is free, but in my experience, to make it work you usually have to train up a model, though the model that comes with it seems to be set up for scanning English book pages, so may be appropriate for library use. OCRopus, from a research group in Germany, seems more powerful than Tesseract, and is also freeware, but is (IMO) currently a pain to set up. And, again, to get good results, you often need to train a model. But it seems to have much more functionality than Tesseract (which may or may not be a good thing :-). If you have Microsoft Office (versions including MS Office 2003 or later but prior to MS Office 2010) on a Windows machine, you also have (had) Microsoft's OCR package, which exposes its functionality through a COM interface, so you can call it from other programs. See http://msdn.microsoft.com/en-us/library/aa202819(v=office.11).aspx Similarly, Google Docs 3.0 offers free OCR via the Google Docs API. I've also tried TOCR, a $100-per-machine Windows-only OCR library from www.transym.com, a British MOD spin-off. Comes as a DLL, plus a simple application, and you can build your own application to use the DLL. Pretty accurate, for printed English text -- gives bounding boxes and word and character confidences. Bill