Sustainable Return on Investment (S-ROI) originated from a Clinton Global Initiative (CGI) Commitment to Action by Impact Infrastructure (ii) CEO John Williams in 2008 and 2009 , who was at the time at HDR, to develop a new public-decision-support metric for the Clinton Global Initiative (CGI). The S-ROI process was developed with input from Columbia University’s Graduate School of International and Public Affairs, and was launched into the public domain at the 2009 CGI annual meeting. Since then, the SROI process has been used by HDR and a growing list of other consulting firms to evaluate the monetary value of sustainability programs and projects with an aggregate value of over $10 billion. Columbia University’s Graduate School of International and Public Affairs reviewed the S-ROI process in 2010. The comprehensive review revealed that the S-ROI process was one of the more comprehensive approaches to sustainability measurement.


My recollection of the genesis of the S-ROI process was John Williams convening a small group of professionals that I was a part of in Ottawa. John challenged HDR’s Chief Economist and myself, as Vice President and leader of HDR’s Canadian economics group, to value green. Cost benefit analysis (CBA) and risk analysis became the backbone of S-ROI. The S-ROI process became a very successful consulting business for the HDR economics group in Canada.

Addition, Standardization & Automation

Cost benefit analysis and risk analysis were useful but a comprehensive S-ROI accounting framework was needed. ii was created in March of 2012 to help develop a standard that could be used for measuring sustainability. Who wins and who loses is important and SROI on its own was obfuscating that. So ii added multiple account cost benefit analysis to address the equity questions. I have written about external forces such as competitive grant programs that are driving the industry towards standards and automation.

ii is a charter member of the Institute for Sustainable Infrastructure (ISI). ii developed the comprehensive SROI accounting framework into the Business Case Evaluator (BCE) for Stormwater into a tool. Stormwater is the first module of the Business Case Evaluator. The BCE provides a value-based and risk-adjusted analysis of stormwater infrastructure projects and maps these to Envision credits. Impact Infrastructure, LLC, has made the BCE available at no-cost to Envision users.


The BCE continues to expand, with ii working on the BCE for transit. ii has also developed the software from the spreadsheet-based BCE to cloud-based AutoCASE. The new software continues to evolve with user-input and a cleaner user interface.

Many of the issues the S-ROI accounting framework is being asked to address now are infrastructure related. ISI‘s Envision rating system deals with city or region wide sustainability issues. ii has moved beyond the SROI framework to quantify value based on distance and interrelationships. This is the growth of the SROI process to Cost Benefit Analysis combined with Building information modelling (CBA-BIM).

In the last couple of posts I have been developing and documenting the literature that supports marrying CBA and Geographic Information modelling (GIS) in a CBA-BIM framework. The willingness to pay (WTP) distance decay function is the key linking function that allows the economic business cases to be put into a geographical co-ordinate system.

SROI has come a long way:

  1. From its roots in the public domain as a CGI commitment to action with Columbia University
  2. To a consulting tool that joined meta-analysis informed CBA and risk analysis
  3. To a framework that added multiple account CBA and was adopted by ISI
  4. To cloud-based AutoCASE
  5. And finally to CBA-BIM.

Nothing has been dropped along the way, enhancements and additions mean that CBA-BIM retains the ability to do everything SROI was intended to do but with the ability to answer more detailed questions. CBA-BIM will be built into ii’s AutoCASE product line to allow users worldwide to answer these questions automatically with cloud-based software and state-of-the-art modelling tools.