What are the best books with a strategic focus on how to transform organisational systems

The roundabout answer is that it depends on what sort of school of thought you’re coming from. There are approaches which seem to promise quantitative returns but are difficult to implement, and there are more holistic approaches and theories that take into account the complexity of the individuals that make up the organizations. This second group tends to include approaches like Appreciative Inquiry, Open Space Technologies and recognizes organizations less as machines than complex and dynamic systems.