Departing from normative notions of participation as passive or responsive vis-à-vis active or agentic, this article conceptualises participation as "'relational investment'". Drawing from a qualitative case study of a culturally and linguistically diverse (CALD) Australian primary classroom, I argue that students' decisions about how to participate are shaped by the nature of their social relationships. Thus, I illuminate all participatory strategies as agentic and subject to the relational conditions of the field. Building on Bourdieu's (1977, 1990, 1992) theorisations of 'social capital' and how this has been mobilised in Norton's (1995) concept of 'investment' (used as a model for language learning), I illustrate the limits of the economic logic of capital embedded in these theoretical tools. Instead, I propose engaging with the notion of 'sociality' (Bottero's 2009) to capture how the characteristics of classroom social relationships shape the ways students invest in participating.