The case study outlines the design and features of Hotel Rahman, located in Phúc Yên, Vietnam, emphasizing its 'forest in the sky' concept that integrates over 75,000 plants into its architecture. The building, which contains 11 floors and various luxury accommodations, is recognized for its sustainability, achieving significant reductions in energy and water usage while utilizing local materials and creating job opportunities for the community. Noteworthy architectural elements include balconies covered in greenery, extensive use of natural daylight, and advanced energy-saving features, positioning the hotel as a green landmark.