Reading the commentary coming from Rio +20, it sounds as if the sustainable development conference, like so many that came before, is disintegrating into the ‘Very Big Corporation of America’ sketch in Part VI: The Autumn Years of the Monty Python film ‘The Meaning of Life’. However, to quote another Monty Python work, there is “a bright side” to look on, because whatever is or isn’t agreed by politicians in Rio de Janeiro this week, positive change is most definitely afoot.