Sustainable development has become more important because the world has realized that changes are needed to protect the environment. It is essential that companies increasingly engage in long-term thinking and take responsibility for the environment. The aim of this study is to determine the approach manufacturing companies and investors have toward sustainability and sustainable investments. The theoretical frame of reference describes approaches within sustainable investments and various instruments within CSR. The study then introduces two theories: the legitimacy theory and the stakeholder theory. These theories can strengthen the CSR approaches in sustainable investments. The study consists of a qualitative research approach since the focus of the study is approaches within sustainability. Furthermore, interviews were conducted with seven different companies to gain views from companies active in different industries. In the empirical study, all seven interviewed companies are introduced and all the collected data is presented. To clarify the empirical study, each company is given its own section to highlight their approaches. The empirical study then presents the similarities and differences between manufacturing companies and investors regarding the research question. After the theory and the data were analyzed, the study concludes that companies relate to sustainability to meet stakeholder expectations. The manufacturing companies and investors work within sustainably as CSR has become an increasingly important area in the business world. A company must consider what the market and stakeholders demand in a sustainable market.