Dhaka, the capital of Bangladesh, is the eleventh largest megacity city in the world, with a population of 18.2 million people living in an area of 1528 km². This city profile traces the trajectories of its urban development to becoming a megacity and characterizes its emerging challenges due to informal urbanization and climate change impacts. Due to rapid population growth and uncontrolled urbanization, Dhaka currently faces various socio-economic and environmental challenges in aspects such as providing basic urban services; reliable transportation framework; constant water and energy supply; effective sanitation; sustainable waste management and affordable housing. Moreover, the urban setting has further deteriorated as Dhaka is already facing various adverse impacts of climate change. Studies predict that most of the urban sectors, public health and surrounding agriculture and fisheries in Dhaka will be severely impacted by climate change. Dhaka is trying to transform its existing “incremental development” model to an “integrated development” framework in order to effectively mitigate its extreme urban challenges. The future of Dhaka city significantly relies on the successful execution of integrated infrastructure and service planning, development, and management practices, operating under an accountable and good governance system.