From the website Vision of Humanity,
The Global Peace Index is a ground-breaking milestone in the study of peace. It is the first time that an Index has been created that ranks the nations of the world by their peacefulness and identified some of the drivers of that peace. 121 countries have been ranked by their ‘absence of violence’, using metrics that combine both internal and external factors. Most people understand the absence of violence as an indicator of peace. This definition also allows for the measuring of peacefulness within, as well as between, nations.[Hat Tip: John M. Lynch]
Peace is a powerful concept. However, the notion of peace, and its value in the world economy, is poorly understood. Historically, peace has been seen as something won in war, or else as an altruistic ideal. There are competing definitions of peace, and most research into peace is, in fact, the study of violent conflict.
Vision of Humanity contains the results from the Global Peace Index and other material of interest on peace. It also contains a section on institutions that need help to fund peace-related initiatives. Over time this source will be updated to combine more relevant material that will demonstrate the linkages between peace and sustainability.