The document discusses efforts by cities in the Helsinki Metropolitan Area of Finland to reduce greenhouse gas emissions and energy consumption through cooperation. It notes that the population and emissions are growing in the area. The main sources of emissions are heating, electricity use, and transportation. It proposes a climate vision and sectoral visions to minimize emissions through improved energy efficiency, sustainable transportation and land use planning, low-carbon building and energy solutions. Specific policies and initiatives discussed include increasing public transit usage, utilizing biofuels in buses and vehicles, retrofitting existing buildings for energy efficiency, and optimizing district heating and cooling systems.