The final report from the IEA 4E Solid State Lighting Annex’s 2017 Interlaboratory comparison (IC 2017). This comparison had 36 participating laboratories from 19 countries with a total of 42 goniophotometric instruments, the largest interlaboratory comparison of such equipment ever undertaken. This comparison investigated the level of agreement in measurements of SSL products by various types of goniophotometers including near-field type and source-rotating type, as well as mirror-type goniophotometers which are most commonly used. IC 2017 used the international standard CIE S 025 (or equivalent European standard EN 13032-4) as the test method for this comparison. IC 2017 was also designed to be in compliance with ISO/IEC 17043 so that it may serve as a proficiency test for SSL testing accreditation schemes around the world. The comparison artefacts used in IC 2017 were (1) narrow beam LED lamp with ≈ 12° beam angle; (2) 60 cm x 60 cm indoor planar LED luminaire, (3) 60 cm long linear batten LED luminaire including small upward light emission, and (4) street lighting LED luminaire having asymmetric intensity distributions.