The workstreams preceding this module have demonstrated how to acquire the latest view for decisions to be made in the near-term using crowd-sourced knowledge harvesting and segment kracqing. This is made from a systematic series of (customised) geo-technical and geo-commercial metrics. If your organisation has made decisions which you would like to replicate or avoid in the future, then an interview based knowledge harvesting approach is recommended. This can be achieved most efficiently if some of those who were involved in preparing the original opportunity are still working for your organisation, although much of the look-back can and should be derived from good investment decision documentation. The same applies if an opportunity was declined. Whatever the source, it is a simple task to compare perspectives before and after to examine the gaps and establish if there are any consistent outcomes that can help to support effective decision making in the future. Generally, the same geo-technical and geo-commercial metrics that were used as business drivers for future opportunity screening should work for a look-back analyses but they can also be changed to suit. An example where this may not work is when commercial strategy has changed since the original decision was made.