The current thesis proposes a gamified approach that encourages the office workers to start saving energy in a collaborative way. They can define sequences of actions to be performed immediately or at a later time and send tailored recommendations to their colleagues, in the form of action sequences. By actively using the application, controlling their workplace in an energy-efficient way and encouraging their colleagues to have a pro-environmental behavior, the users enter a competition. The gamification strategy used in the current application makes use of game mechanics elements such as points, badges, levels and high scores. The pro-environmental behavior of the users is rewarded with points and/or stars. By accumulating points, they can climb in the high scores. Each player starts the game with five empty American flags, without stars on the canton. By accumulating stars, they can fill in the flags one by one and advance to the next level.