You have probably never heard of the Theory of Constraints (TOC).
Developed by Eliyahu Goldratt and first revealed in The Goal, it is one of the most effective approaches to business development. It also provides some of the fastest and most cost effective development available.
Many of the solutions revealed by TOC are counter-intuitive (see the aticle on Profit v ROCE) which explains some of the reason why they have taken so long to gain traction.
I shall be producing a series of articles on the subject of TOC but this will take time so I have been looking for some introductory content on the theory.
The video below is a pretty good starting point.