CLIVAR is celebrating 20 years of progress since publication of its first SciencePlan in August 1995. To mark the occasion, past SSG co-chairs have contributed articles on an aspect of the CLIVAR project that they felt made particular strides during their tenure. Their reflections take us from the roots of CLIVAR in the late 1970s and 80s (the days of FGGE, TOGA and WOCE),  through  the revolutionary advances of the 1990s, to the modern era of climate services. Download Exchanges 70 here.