The principal task of the CIPM is to promote world-wide uniformity in units of measurement and it does this by direct action or by submitting draft resolutions to the General Conference.
The 2007 MoU between the CIE and CIPM was to ensure that data related in particular to measurements of light, optical radiation, colour, optical properties of materials, photobiological and photochemical quantities are properly based on units traceable to the SI, and to maintain consistency between the publication "Principles Governing Photometry" prepared by the CIE JTC-2 Joint CCPR-CIE Task Group and the SI Brochure.
The CIE paticipates in the CIPM's Consultative Committee for Photometry and Radiometry (CCPR) and the Consultative Committee on Units (CCU).