To adopt the interconnected dimensions of the corporate sustainability approach and to have a successful sustainability performance, businesses need varied resources and partners. NGOs have become an important strategic partner for businesses in designing and implementing corporate sustainability activities. Based on the corporate sustainability approach, this study aims to examine the reasons and the consequences of business-NGO collaborations through the relevant literature and the case study methodology. Supporting previous research the examined cases-Turkcell, Vodafone, Türk Telekom cooperates with NGOs for strategy implementation, legitimacy assurance, resources and skills access, social benefit and new product/market development. Further, the companies can reach many consequences that can create competitive advantage as integrating sustainability to strategies, enhancing legitimacy and performance, increasing brand equity, attracting and retaining quality human resources and improving innovation capability thanks to collaborations formed with NGOs. Additionally, it was found that the examined companies mostly interact with sectoral NGOs and they only have a few interaction related to eco-innovation, a rising issue in the industry.