G.P.S. is an extremely elaborate and realistic simulation of the functioning of the planet. All of the countries of the world are represented with their own variables and manners of functioning. The player is head of a country's government (president, king, prime minister, etc.) and can act in all domains: economic, social, military, foreign and domestic politics, environment, cultural, etc. Two game modes are offered to the player :
- Free mode: The player's objective is to remain in power as long as possible and to further his influence throughout the world.
- Scenario mode: several scenarios and missions with different difficulty levels and with specific objectives are proposed to the player. The game can be played in « solo » mode against the computer or in multiplayer mode (up to 16 players).
- Scenarios: 30 original scenarios and missions ranging from global environment stability, energy shortages, the spreading of new diseases, terrorist threats, economic wars, military invasions, nuclear catastrophe, etc..
- Interface: Inspired by information TV programs with multiple windows, on-screen video inserts, scrolling ticker tapes, ID cards for countries and personalities, etc.
- Player actions: The player has a number of actions at his disposal, depending on how each country operates.
- Wargame: Military operations are performed directly on the map.
- Game engine: To calculate the developments of the planet's values, economic equations and statistical diagrams are used.