The document discusses co-optimization, which is integrating, measuring, and optimizing paid search and organic search keywords simultaneously to maximize their collective potential. It provides examples of companies that saved hundreds of thousands in PPC budgets or saw incremental SEO revenue by aligning their paid and organic keyword data and strategies. The document advocates assessing the current state of a company's keywords, analyzing proximity performance when keywords rank in both paid and organic, finding anomalies in high-converting keywords, and maximizing the search results page shelf space through collaboration between paid and organic listings.