The document discusses responsive design from a marketer's perspective. It defines responsive design as providing an optimal viewing experience across devices through flexible layouts that adapt to different screen sizes. The key benefits of responsive design are meeting mobile user expectations, reaching mobile-only users who spend more time on mobile devices, and improving SEO. Most industries should consider responsive design, though some retailers may find mobile-optimized sites better. Responsive design requires additional time and costs compared to a typical website redesign.