Mathematics education as a matter of identity’ is an emergent field where selfhood and the mathematical subject are being theorized as the effect of lived experiences in institutions such as family, school, media or youth cultures. Identity and its associated term subjectivity are embryonic in varied theoretical and activist arenas ranging from sociocultural psychology, psychoanalysis, cultural-studies, post-structuralism, post-colonialism, new-materialisms or arts-based-research. Emphasis on the ‘question of the subject’ facilitates the problematizing of a ‘knowing self’ as the effect of politics of difference, diversity, language, discourse, body, power, authority, agency, justice and emancipation, or as the product of affective politics connected to consumption habits and entertainment desires. Up until today, ‘identity’ persists the status of a ubiquitous concept in social sciences, resists clear-cut definitions and subjects itself to critique. Despite being unsettled as a robust concept, mathematics education researchers embrace identity and/or subjectivity towards analyzing, discussing or interrogating how selfhood becomes inscribed through mathematical practices, how certain subject positions are constructed as normative, deficient or marginal and how a reconfiguration of mathematical subjectivity is potentially possible as part of cultural, discursive, material, corporeal, or affective renewals. Moreover, ‘mathematics education as a matter of identity’ is key towards understanding the reciprocal relation amongst a bourgeoning free-market economy, neoliberal governing, increased socioeconomic crisis, vulnerable environmental sustainability, loss of security and safety, forced migration and a risky process of fabricating (by means of mathematics) the rational, reasonable and yet fragile, fragmented or indebted subject.