The article examined three widely accepted approaches to sustainable investing: Socially Responsible Investing (SRI), Environmental, Social and Governance (ESG), and impact investing. Nevertheless, these sustainable investment strategies are under-institutionalised, characterised by a lack of consistent terminology and mixed return performance. Given that these inconsistencies are prevalent in academic research regarding sustainable investing, the paper aimed to perform a systematic review of related studies to compare, contrast and consolidate these sustainable investment approaches. The findings of this study reveal overlapping conceptual frameworks between SRI, ESG and impact investing. The paper recommends the development of a consistent conceptual framework for sustainable investing.