Over the past two decades, southern Africa has experienced both exceptionally high AIDS prevalence and recurrent food shortages. International institutions have responded to these challenges by framing them as security concerns that demand urgent intervention. Young people are implicated in both crises and drawn into the securitisation discourse as agents (of risk and protection) and as (potential) victims. However, the concepts of security deployed by global institutions and translated into national policy do not reflect the ways in/security is experienced 'on the ground' as a subjective and embodied orientation to the future. This paper brings work on youth temporalities to bear on social and cultural geographies of in/security and securitisation. It reports on research that explored insecurities among young people in Lesotho and Malawi. It concludes that, by focusing on 'threats' in isolation, and seeking to protect 'society' as an abstract aggregate of people, global securitisation discourses fail either to engage with the complex contextualised ways in which marginalised people experience insecurity or to proffer the political responses that are needed if those felt insecurities are to be addressed. However, while securitisation is problematic, in/security is nonetheless an important element in young people's orientation to the future. Inquiétudes pour l'avenir: l'incommensurabilité de la sécurisation et des in/sécurités chez les jeunes Africains du sud RÉSUMÉ Ces deux dernières décennies, le sud de l'Afrique a connu à la fois la prévalence exceptionnellement haute du SIDA et des pénuries fréquentes de nourriture. Les institutions internationales ont répondu à ces défis en les considérant comme des enjeux de sécurité requérant une intervention urgente. Les jeunes sont impliqués dans ces deux crises et inclus dans les discours de sécurisation comme agents (de risque et de protection) et comme victimes (potentielles). Pourtant, les concepts de sécurité mis en oeuvre par les institutions mondiales et transformés en politique nationale ne reflètent pas les manières dont