Résumé : Social innovation is increasingly believed to have a great potential for addressing persistent societal challenges such as sustainability, social inclusion, democratization and deprivation. We understand transformative social innovation (TSI) as social innovation that is aimed to challenge, alter, replace or provide alternatives to dominant institutions and structures. Efforts to institutionalize TSI ambitions tend to lead into a grey zone between transformation and reproduction. This contribution will follow earlier explorations into this territory that work with dialectical perspectives. As preparation for a broader comparative case study, we compare institutionalization dialectics as they unfolded in the cases of the Basic Income and Timebanks. We conclude with preliminary observations on these two cases, and evaluate how the dialectical framework helps to gain systematic insight into TSI institutionalization.