I've been giving some careful thought to why it became necessary to create the concept of Enterprise Services Planning, ESP for short.
At the most fundamental level, ESP was necessary to provide a container for the collection of things we were teaching that were beyond kanban systems and beyond the scope of the Kanban Method. These were the things that enabled the optimal and effective use of kanban systems - topics such as: probabilistic forecasting and statistical analysis; qualitative risk assessment; real option theory; connecting strategy to operational mechanisms such as Kanban capacity allocation; and so forth. ESP represents a system of management for an entire professional services business. It isn't just an IT thing and it certainly isn't just for operational management of a single service delivery workflow. So we needed a name that encompassed concepts that were a lot bigger than Kanban.