HICCuP HICCuP is a powerful CIF checking program written at the CCDC, which is freely available to the crystallographic community. It is hoped that by providing HICCuP and promoting its use to test CIFs we can improve the conformity of CIFs submitted to journals and those sent to the CCDC as direct depositions. Ultimately, this will improve our ability to provide an up-to-date database for all our subscribers. The HICCuP interface provides a list of all the CIF data blocks in the selected file. These blocks are colour coded as the checking process proceeds. An integral "CIF aware" editor and on-line CIF dictionary can be used to correct any errors. Once corrected, the CIF can be saved to disk ready to be stored locally, sent to a journal or deposited at the CCDC. HICCuP is written in Python and is supported on many platforms including almost all UNIX systems, Macintosh and Windows 95/NT. It can also be easily implemented on other systems. To obtain a copy of HICCuP simply download from this Web Site. Send comments and questions about this web site to webman@ccdc.cam.ac.uk