When approaching a green buoy what side must you approach it?

When approaching a green buoy, you should pass it on your port side (the left side of your vessel when facing forward). This is part of the IALA (International Association of Lighthouse Authorities) buoyage system, which indicates that green buoys mark the left side of a channel when entering from the sea. Remember, red buoys should be kept on your starboard side (right side) in the same scenario.