Sustainability is the newest challenge for the humankind. It poses an existential threat to everyone, cutting across developed and developing countries. Considering the immense clout business enjoys in the present world order, corporations have a greater role to address sustainability challenges. 'Talking the Walk' and 'Taking the Walk' toward Responsibility: Sustainable Development through Core Competency based Business Responsibility is an attempt to explore corporate world engineered interventions for sustainable development, which are widely known as corporate social responsibility (CSR) or corporate citizenship. In this book, I have addressed: why are corporations strategic to sustainable development? Why are they increasingly manifesting their commitments and pledging their contributions towards the socio-environmental issues? How are they embarking on these non-financial (but business) objectives? How can CSR potentially build win-win propositions both for the shareholdersand the stakeholder? And finally is CSR a fact or a fad in the quest toward sustainable development? Being responsible while adhering to core competency is the key to create sustainable development.