The ICC profile format specifies the widely used ICC color profile for transforming color data between different devices and color spaces. Ambiguities in the previous version were resolved in the v4 specification, which also introduced a perceptual reference Medium to provide a well-defined intermediate gamut as a target for gamut mapping and re-rendering between source and destination data. Since the first publication of the 4 specification, there have been a number of important amendments, which collectively move the ICC color management architecture further away from its original static processing model to a more dynamic and flexibly programmable one. With the new colorimetric intent image state tag, it is possible to identify transforms which are suitable for images in an input-referred image state and which need to be processed according v. ICC also provides an on-line profile registry now, a permanent repository of profiles for standard printing conditions. The registry supports both manual selection and automated download of profiles The floating-point device encoding range amendment introduces support for floating point data, but also introduces a new and potentially more extensible form of color transform, known as multiprocessing elements. In the future these may be extended to provide a range of color processing capabilities that are not currently available. This is an important component of the smart and programmable CMM concept, in which the color matching module uses data in the profile as well as rides and other information to construct the most suitable transform for the image, workflow, and user preference. (c) 2008 Wiley Periodicals, Inc. Col Res Appl, 33. 444-448, 2008: Published online in Wiley InterScicnce (www.intersciericc. wilcy.com). DOI 10.1002/col.20446