3747 20190114171323.0 SCART-2019-0031 Antoja, T. Gaia DR2 documentation Chapter 10: Catalogue validation 2018 This chapter of the Gaia DR2 documentation describes the tests which have been applied, together with the results mostly obtained on preliminary data, and which contributed to improve the published Gaia DR2 catalogue. Main validation results have been published by Arenou et al. (2018) and this chapter provides complementary details. NO Arenou, F. Babusiaux, C. Barache, C. Bossini, D. Breddels, M. Cantat-Gaudin, T. Diakité, S. Fabricius, C. Fabrizio, M. Helmi, A. Jordi, C. Leclerc, N. Luri, X. Marrese, P. M. Massari, D. Mignard, F. Muraveva, T. Pauwels, T. Reylé, C. Robichon, N. Robin, A. Romero-Gómez, M. Sordo, R. Soria, S. Spoto, F. Tanga, P. Turon, C. Vallenari, A. Veljanoski, J. Gaia DR2 documentation, European Space Agency; Gaia Data Processing and Analysis Consortium. 2018 ronny.blomme@observatoire.be http://adsabs.harvard.edu/abs/2018gdr2.reptE..10A https://gea.esac.esa.int/archive/documentation/GDR2/ published in NONREF