"Top-down" and "bottom-up" are ways to think about linking strategy and the product portfolio. In a top-down approach, strategic decisions are made at the highest level and then cascaded down to influence the product portfolio and project selection. In contrast, a bottom-up approach involves gathering input from lower levels of the organization, including insights from product teams and market feedback, to inform strategic decisions. Both approaches are used to ensure alignment between the company's overall strategy and its product development efforts, fostering coherence and strategic alignment (Ansoff, 1987; Mintzberg, 1994).