PurposeCorporate responsibility and sustainability (CRS) have emerged as an important topic today. At the same time, alliances and coopetition arrangements, as vehicles for inter-firm collaboration have been shown to support firm performance. Still, there has been a lack of research into how coopetition (collaboration with competing firms) in this area may support firm performance.Design/methodology/approachThis study aims to untangle the relationship between coopetition arrangements including CRS and firm performance. The model permits garnering social performance, which is a key to CRS, and to move beyond the traditional view of the coopetition–firm–economic–performance relationship. This study is based on a survey and primary data from 215 firms in Australia. This study uses multiple indicators for the concepts. Relationships are estimated by multiple regression analyses.FindingsUsing survey data from 215 firms in Australia, the research findings confirm that coopetition in CRS can lead to improved firm performance, both in relation to financial and social performances. However, the association between coopetition in CRS and financial performance loses its significance when social performances is introduced as an additional control variable. Further, stakeholder attributes (i.e., effective power and legitimate stake) moderate the relationship between coopetition in CRS and firm financial performance. However, there was no evidence of moderation for the coopetition in CRS – firm social performance relationship.Research limitations/implicationsThis study contributes to both coopetition and corporate social responsibility research. This study demonstrates that improved firm performance may be achieved through the promotion of CRS initiatives when a coopetitive approach is adopted, particularly where an understanding of stakeholder attributes is also evident. Firms do not need to shoulder corporate social responsibility alone. They need to find well-fitting partners. There are new ways to improve sustainability in terms of nature and human relationships.Practical implicationsFirms do not need to shoulder Corporate Social Responsibility (CSR) alone. They need to find well-fitting partners.Originality/valueThis study provides very novel insights by having integrated the literature on coopetition, corporate social responsibility and sustainability resulting in a new conceptual framework that combines coopetition in CRS and performance. The new conceptual framework has both practical and research implications for coopetition in CRS and firm performance.