Hanoi, Aug. 3 -- Sustainable tourism is becoming a defining trend among Vietnamese travellers as they increasingly seek to balance memorable experiences with positive contributions to local communities and the environment, according to Booking.com's 11th annual Travel & Sustainability Report. The report points to a shift in travel behaviour, with holidays no longer seen solely as opportunities for leisure but also as a way to support local economies, preserve cultural heritage and reduce environmental impacts. According to the online travel platform, 85% of Vietnamese travellers consider sustainable travel a priority, while the same proportion want their trips to leave a positive impact on destinations. Based on a survey of 32,500 respond...