We propose a model for solving a parcel delivery problem with a fleet of trucksembedded with drones. When appropriate, drones are loaded with a parcel, launcheddirectly from the truck, and sent to a client. Afterward, the drones autonomouslyreturn to the truck to be replenished and recharged. Inspired by the case of a largeEuropean logistics provider, the proposed modeling framework confronts realis-tic delivery problems involving time windows, limited drone autonomy, and theeligibility of clients to be served by drones. The considered global cost functionincludes fixed daily vehicle fares, driver wages, and the fuel and electricity con-sumption to power trucks and drones. To solve the problems at hand, we proposea mixed-integer linear programming formulation and an adaptive large neighbor-hood search. Moreover, we introduce an efficient modeling framework to managethe numerous synchronization constraints induced by the simultaneous use of trucksand drones. We analyze the benefits of this new transportation concept for deliveryproblems involving up to 100 parcels. Results show that truck-and-drone solutionscan reduce costs up to 34% compared to traditional truck-only delivery. From a man-agerial perspective, we show that a certain percentage of client locations must bereachable by drone to make truck-and-drone solutions competitive (i.e., if the fixedcosts of the drones are compensated for by the savings on truck routes) and comparethe cost structures of truck-and-drone versus truck-only solutions