The 15 Global Challenges have been identified and updated through an ongoing environmental scanning, Delphi process, expert opinions, and interviews since 1996. They represent a cumulative and distilled range of views from over 4,000 participants from around the world. Full details of the questionnaires and interview protocols that have been used from 1996 to 2009 to generate both the short and more detailed treatments of these Challenges are available in the Global Lookout section. Since 2010, The Millennium Project used a continuous online Real-Time Delphi process, environmnetal scanning, dedicate listserves, and the Global Futures Intelligence System (GFIS) for the continuous update of the Global Challenges.

The following diagram presents the process on how the 15 Global Challenges were identified and the continuous work ever since.

Short History:

1996-1997: The Millennium Project asked an international panel of eminent futurists, scholars, and decisionmakers which are the most important issues facing humanity. The process consisted of through literature review, several rounds of Delphi, and interviews. The results were 182 developments, with 131 actions to address them. For greater cohesion, these were distilled into 15 Global Issues.

1997-1998: Through a similar proces as in the previous year, The Millennium Project asked which are the most important opportunities facing humanity. The results were 180 developments, with 213 actions to address them. For greater cohesion, these were again distilled into 15 Global Opportunities. Note: the fact that the results were again 15 was pure concidence.

1998-1999: At the 1998 Millennium Project Planning Committee it was decided that the 15 Global Issues be merged with the 15 Global Opportunities, so that a more condesed list results with items to be followed through time to assess change — progress or regress in different domains and the global situation as a whole. The result were the 15 Global Challenges with 213 actions to address them. Note: again, the number of 15 items and 213 actions was pure concidence; there was no previous number objectives set.

1999-2000: For better description and easier understanding, a structure was set for each Global Challenge: a general overview of the situation and potential trends; regional specifics and trends; actions to address the challenge; specific comments or relevant papers; indicators to follow progress.

2000-2001: The process for assessing progress on each challenge and the global future as a whole has been developed. A Delphi study was conducted to determine which are the best indicators to assess progress (or regress) for each challenge, and which are the best and worst values for those indicators in 10 years.
Ted Gordon developed the State of the Future Index (SOFI), which integrates into one index the most relevant indicators to measure change of the global challenges. SOFI is a measure of the 10-year outlook for the future based on historical data for the last 20 years. It continues to be computed and developed ever since.

2001-2012: The updating of the Global Challenges continued, being published in the annual State of the Future reports. For easier reading, a short overview of the challenges with regional considerations was published in the print sections of the report, while the increasingly detailed and more documented research was published in the CD accompanying the reports.
The SOFI also continued to be computed and further developed each year. Over the years, it has been improved by adding the Trend Impact Analysis, writing scenarios, and computation of national SOFIs for several countries.

Since 2012: the process of updating of the Global Challenges has been improved by completely moving it into cyberspace, as part of the Global Futures Intelligence System (GFIS) Here, references are linked directly to the source, and each challenge has a review panel that continuously updates the content and reviews the suggestions provided by other readers or participants. Therefore, the Global Challenges emerge as a global collective, independent, objective, and well-documented view of the world situation and perspective, with suggested actions to address them, sources for further details, relevant organizations and news sources, as well as the possibility of the public to contribute their own views or conduct dialog with experts on specific issues of interest.

SOFI continues to be computed each year. A Real-Time Delphi is conducted before each computation to collect opinions on the indicators and values to be included, as well as potential actions to improve the global future.