Corporate Social Responsibility (CSR) is a business approach contributing to sustainable development through economic, social, and environmental improvements. The Companies Act, 2013 (Section 135) mandates CSR spending of 2% of average profits for qualifying companies. CSR activities include education, healthcare, environmental protection, and community development. The CSR Committee must approve CSR policies, and Board must ensure implementation. Key distinction: CSR differs from charity—it's strategic and linked to business operations. Companies must prepare CSR reports and disclose spending annually. Landmark case principles show CSR as addressing regulatory, ethical, and discretionary expectations. ICAI members advise companies on CSR strategy and compliance. Practical application: Companies must establish CSR policies, implement projects, monitor outcomes, and report transparently. Exam tip: Understand CSR as mandatory compliance (not voluntary) for qualifying companies; focus on Section 135 requirements and the policy-setting process rather than just project examples.