Billions of people worldwide, and tens of millions of Nigerians, still live in communities where electricity is unreliable, connectivity is thin, clinics are distant, farm yields are low, and public services arrive late or not at all. These communities are not underserved because they lack ideas or industry; they are underserved because the systems built to reach them were designed elsewhere, by single disciplines, for different conditions. This keynote paper argues that closing the gap requires innovation that is simultaneously technical, social, economic and institutional. It proposes a five-layer framework: energy and connectivity as foundations, data and artificial intelligence as multipliers, sector applications in agriculture, health, education and water, enabling institutions and policy, and community ownership at the centre. Drawing on examples from Nigeria and the wider continent, the paper discusses the opportunities and risks of artificial intelligence for underserved areas, the role of engineers, universities and professional bodies such as the Nigerian Institute of Electrical and Electronic Engineers (NIEEE), and the barriers that routinely derail otherwise sound projects. It concludes with a practical ten-point roadmap and a call for a university-industry-community collaboration in which institutions like the Federal University of Agriculture, Abeokuta, serve as living laboratories for solutions that can be scaled.