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This dissertation examines opportunities for buyers to actively influence supplier corporate social responsibility (CSR) practices. Investigating the conditions under which CSR commitment and socially responsible purchasing (SRP) practices spread upstream along a given supply chain, we use institutional theory, the resource-based view, and transaction cost economics to develop and test three alternative causal models, including moderated, mediated, and direct effects of the buyer-supplier SRP relationship. We find buyer SRP to constitute a driving force of CSR behavioral alignment among the single actors of a supply chain and demonstrate empirically that buyer SRP can have a considerable effect on supplier SRP performance. Succeeding at such an endeavor depends on a firm´s external environment, firm internal factors, and the core TCE factors of asset specificity, behavioral uncertainty, and transaction frequency.

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