The successful gravity mission GRACE is reviewed from a perspective of an end user. It is observed that the high-quality, easy-to-use solutions that have been continually provided by the analysis centers contributed to the widespread use of the GRACE data, especially among non-specialists, which resulted in vast amount of fruitful scientific findings by the mission. The author feels a successful analysis center, that is able to provide high-quality data, needs a team that includes both the specialists of the raw data analysis and those of data evaluation/interpretation (and those who know both, of course). Such a team will also be critical for the success of a future Japanese mission.