Reinventing the Post: Building a Sustainable Future is the third book in this series which explore how the postal sector is changing in order to meet new challenges. This volume addresses the fundamental issues which face the sector, not just to survive but to have sustainable economic business models that will secure a future for the industry and continuing work for its employees. This in turn benefits other stakeholders and society as a whole whilst also taking care of the planet by making less use of scarce resources and reducing negative environmental impacts.  The postal sector has an enormous impact on the daily life of nations, businesses and households reaching right across countries, lubricating economies, providing universal services accessible to rural and city communities and employing millions of people.  When taken together with related businesses and sectors, it has a vast daily ‘footprint’ across the globe, covering every aspect of life.  So much so that it can, almost uniquely and by itself, be a very powerful agent for change and arguably a vehicle with more traction and prospect of moving things forward than inter-governmental initiatives that rely for their momentum on political agreements to aspirational targets. If the sector collectively changes its thinking and behaviour, it can take its employees, customers and suppliers with it, along with all the people and activities associated with them. So this volume is more than showcasing perspectives from the industry to stimulate and challenge thinking about sustainability, it is also a call to action for the whole of the sector to play a major global leadership role in facing the very real existential threats to our planet and life on earth.  This will take much more radical thinking and imagination than we have applied to reinventing the post or developing new business strategies – it requires us to face some very fundamental questions about our very existence.