This research work critically evaluates the alignment of Corporate Social Responsibility (CSR) with strategic business applications to foster inclusive and sustainable development. The purposes of this study are to (1) examine the development of CSR in relation to SDGs and ESG frameworks, (2) assess CSR implementation across various sectors, (3) evaluate its impacts on stakeholders and sustainability, and (4) bridge the gap between the theory and application. This research employs a qualitative, multiple-case study method to examine cases of six corporate houses: Unilever, Patagonia, ITC Limited, Dabur, Reliance Foundation, and a comparative comparison of SBI and Axis Bank. The study utilises thematic content analysis of CSR reports, academic literature, and ESG disclosures. Significant findings reveal that Unilever minimised CO₂ emissions by 65%, Dabur recycled more than 12,400 tons of plastic scraps, and ITC positively impacted over 6 million people via rural projects. SBI and Axis Bank together spent more over ₹1,000 crore in CSR from 2017 to 2024. These findings validate CSR's potential to enhance brand equity, operational resilience, and social legitimacy. However, the projects face several challenges concerning greenwashing, regulatory compliance, and ineffective impact assessment. The study calls for standardised ESG reporting, fiscal incentives for validated social impact, and stakeholder-oriented governance. Future study should be conducted on longitudinal impact studies, digital CSR instruments, and behavioural reactions to corporate sustainability.