The Design of Competitive Online Algorithms via a Primal-Dual Approach extends the primal-dual method to the setting of online algorithms, and shows its applicability to a wide variety of fundamental problems. Among the online problems considered are the weighted caching problem, generalized caching, the set-cover problem, several graph optimization problems, routing, load balancing, and the problem of allocating ad-auctions. There is also an illustration of how classic online problems such as the ski rental problem and the dynamic TCP-acknowledgement problem can be solved optimally using a simple primal-dual approach. The Design of Competitive Online Algorithms via a Primal-Dual Approach is an invaluable reference for anyone working in the area of computational theory, and especially those interested in exploring online scenarios that can benefit from the primal-dual framework.