Strategic sustainability communication in organizations managed by financial objectives is characterized by paradoxical tensions that arise within the organization when sustainability goals are added. Yet the dominant perspective on sustainability among practitioners and researchers is the Business Case Frame (BCF) which is ill-suited to address these tensions. This chapter is built on a qualitative study of sustainable investors’ approach to paradoxical tensions in their business. The interviewees are Swedish members of the Climate Action 100+ project, an investor-led engagement initiative on climate change. The theoretical base is formative approaches to communication that regard it a sensemaking process where sustainability talk and practice constitute each other and meaning is continuously negotiated. Formative approaches to sustainability communication have come as a reaction to the dominance of instrumental, functionalist research perspectives. The results indicate that investors have no objection to a BCF, although they confirm a potential conflict between sustainability and financial goals that are sometimes realized. Still, a BCF limits the ability of sustainable investors and companies to operate under the complex circumstances and contributes to the problems rather than solving them. I propose an alternative to the dominant BCF and develop knowledge about formative sustainability communication by using the theory in a new field as it studies investors rather than companies in an inter-organizational rather than organization-centred context.