Our Carnival Imagination cruise was enjoyable in all respects - except for one thing. We stayed in an ocean view room at the back of the ship. Little did we know that crew members used the balcony above us for their smoking breaks. We discovered this as smoke was blown into our room from the air conditioning/ventilation unit. Our complaints to Guest Services went unanswered as they had no extra rooms to move us to and could do nothing with the crew and their breaks. They apologized profusely and ionized our room nightly, but smoke drifted into our room around the clock. It ruined what was otherwise a perfect cruise experience.