D4L

What if living longer meant living better—more creatively, meaningfully, and connected to others? D4L: Exploring Design for Longevity invites readers to rethink aging not as decline, but as a design opportunity. As longer lives reshape how we work, learn, and plan, traditional age-based models of retirement and aging no longer reflect lived reality. This book introduces Design for Longevity (D4L)—a human-centered, systems-oriented approach to imagining and shaping purposeful life journeys across evolving life stages. At the heart of the book is the D4L Unclock Framework, a flexible design tool that reimagines time beyond linear timelines. It explores three pillars—longevity, service, and system—through the lenses of design, technology, and society. The resulting relationships help readers uncover connections between personal well-being, social infrastructure, and long-term planning. Rather than prescribing fixed solutions, it encourages reflection, exploration, and adaptive thinking over time. Blending personal stories, design research, and real-world projects from MIT, IDEO, and global collaborators, Sheng-Hung Lee presents practical frameworks, tools, and case studies—from Longevity Planning Blocks to LongevityTech cities and phygital experiences. Written for designers, researchers, educators, students, and anyone curious about living longer with intention, D4L offers inspiration and guidance for designing lives, communities, and systems that honor longevity as one of the defining opportunities of our time. This book is a open access book.