This chapter discusses the strategic decision of whether firms should integrate activities internally ("make") or use external suppliers ("buy"). Transaction Cost Economics (TCE) argues integration depends on minimizing transaction costs based on factors like asset specificity, uncertainty, and opportunism. Horizontal integration occurs through mergers in the same industry, while vertical integration moves upstream/downstream. Outsourcing involves moving activities to external suppliers. Firms must consider capabilities, resources, costs/risks, and benefits when deciding to make or buy.