Five leading international property companies have announced an initiative to develop a Global Green Rating system to better evaluate their properties environmental performance. The companies involved are AEW Europe, AXA REIM, Bureau Veritas, GE Real Estate Europe and ING Real Estate. The ratings will be based on measurable indicators related to the building’s functioning, notably energy, carbon, water, waste, health and transport. Once the values are established improvements can be calculated on both a property and portfolio level.