Global mean temperature has risen to about 1℃ above its pre-industrial level and we are experiencing more severe and frequent extreme weather events. If we continue to emit greenhouse gases(GHG) at current levels, it is most likely that we will face irreversible climate by the end of the century. In order to avoid this climate risks, various national and local governments along with civil societies announced ‘climate emergency’ and are asking for more radical action. 
Seoul has played a leading role in reducing GHG emissions and transforming conventional energy systems by initiating innovative climate policies such as One Less Nuclear Power Plant(2012), Seoul’s Promise(2015), Solar City(2017). Despite many successful implementation of many of those policies, Seoul has been slow in achieving its climate goal of 40% emissions reduction by 2030. Furthermore, the city as a member of the C40 must join the global efforts to cap the global temperature rise at 1.5℃, this requires that our society is carbon neutral by 2050. This research aims to suggest key policies for achieving Seoul’s carbon neutrality by 2050, these policies are based on a series of discussions that took place in the ‘Climate Action Forum’ (Nov. 2019~May 2020), which can be summarized as follows:
First, zero energy remodeling for existing building stock is major task if we are to meet the city’s bold climate goal. Retrofitting public buildings including their welfare facilities needs to be accelerated. Along with strengthening the BRP loan program, effective regulations such as an ‘emission cap’ and mandatory ‘energy performance certificates’ should be introduced. 
Second, it is necessary to develop a roadmap to phase out ICE cars, starting with commercial vehicles. It is key to reduce the passenger car driving and to facilitate a transition to low-emission vehicles through more active traffic management policies, such as mileage-based taxation, new carbon free zones, green traffic mileage etc. Restructuring urban road system for pedestrians, bicycle, and new modes of mobility is also important task. 
Third, the city needs to reduce disposable products and encourage re-usable products to achieve the goal of no single-use plastic. In order to achieve the goal of zero inflammable waste to landfill, waste reuse should be increased and wastes that cannot be reused should be efficiently recovered to energy. In addition, re-and up-cycling centers need to be created at the district level to encourage practice of reuse and repair. 
Fourth, in order for Seoul to achieve 5GW of PV by 2050, it needs to convert almost all buildings to produce solar energy. PV should be mandated for public buildings and the current incentive scheme needs to be reformed to subsidize new technologies such as BIPV and light-weight PV systems. Incentives for fuel cells to be installed at buildings also needs to be provided to allow them to be commercially viable. In addition, Seoul needs to promote new business models such as energy prosumer, virtual power plant, and demand response(DR). 
Fifth, city’s climate, energy, particulate matter policies need to be integrated into a single ‘Emergency Plan for Climate Risk,’ this will entail significant organizational and budgetary reform. In particular, deputy mayor for climate change position needs to be created to oversee and coordinate climate policies that are currently conducted in a somewhat fragmentary way. The city needs to enhance its education and learning programs for city officials, citizens, and businesses so that they can actively participate in the city’s diverse climate programs.