It means...

A sustainable food system (SFS) is a food system that delivers food security and nutrition for all in such a way that the economic, social and environmental bases to generate food security and nutrition for future generations are not compromised. Sigrid Stagl has applied social psychology models and agent-based modelling to understand food demand and food supply decision making.

My focus:

Fostering the transition towards sustainable energy systems is central to addressing climate change and other pressing societal issues.