In planning for PDF-3, the International Centre for Diffraction Data's full pattern database of raw diffraction data, it is evident that a standard format for storage and exchange of diffraction data is necessary. An evaluation of the JCAMP-DX protocol by a task group* of the International Centre for Diffraction Data has resulted in a set of format cooes specific to X-ray diffraction. The proposed structure of the data is divided into four parts: the minimal component set required by the JCAMP-DX definition (name, data, owner, sample identification, data type, etc.), a minimum item set required to define the X-ray diffraction data, an open selection of requested but not required information on the sample, its preparation and the instrument, and finally the data itself in one of several specified formats. All information stored in JCAMP-DX format is in ASCII characters. Therefore, these data are printable, easily read by the user and compatible with almost any computer or media storage device. Codes defining the information are primarily in shortened, but readable, English. The task group is completing the work on this project and will be presenting its proposals to JCAMP.