It seems quite difficult to define what 'sustainability' is:
Futures Forum: The semantics of sustainability: 'sustainable development'... or 'sustainable growth' ... or 'sustained economic growth'... or 'development for sustainability'...
Futures Forum: Development for Sustainability: sustainable communities
Futures Forum: VGS AGM: sustainable development: the bigger picture
Futures Forum: Sustainable Development: it's a controversial topic...
Futures Forum: Sustainable Development: a problem of definition
Within the context of the Parliamentary inquiry into the National Planning Policy Framework:
Parliamentary Inquiry | Community Voice on Planning
MPs launch inquiry after research questions ineffective Government planning targets - News from Parliament - UK Parliament
Futures Forum: Parliamentary review on the NPPF: deadline Weds 8th May
Futures Forum: Sustainable Development: and the NPPF
... the Community Voice on Planning has addressed the issue of 'what is sustainability':
Sustainability | Community Voice on Planning