The technological, strategic and administrative innovation needs of the Spanish Navy of the eighteenth century, had implications in the recruitment, preparation and training of officers and sailors, as well as in the general conditions of work and life on board in warships. Some realities were particularly difficult considering the long period of armed conflict that characterized the century. Often under very harsh conditions, the fleets were required to be active and the men were forced to perform difficult and exhausting tasks for the maintenance and handling of the ships, a well as for the marine and military preparation. Observing various aspects of the organization of the service, as well as some dynamics within ships related to food, health, permits, discipline, etc., allows us to better understand their role for the projection of the Royal Navy as a naval force during that period.