The beginning of the 21st century presents the interwoven challenges of climate change, rapid population growth and increasing freshwater, food and energy pressures. These challenges will be discussed as will the manner in which humanity has sought to meet them so far and is likely to do so in the future. The interconnection between climate change and energy use is producing innovative alternative energy ideas which are rapidly gaining ground. This promises to impinge favourably on freshwater and food supply and to ameliorate climate change. There is reason to be cautiously optimistic.