The SI:D3 methodology helps manage complex railway programmes in the context of a fragmented rail industry.

Figure 1 – Great Britain Rail Industry Structure

Source: House of Commons Library, Quick guide to the railways, July 2012

Figure 2 – Model of multi-organisational ‘industry-level’ system integration

Figure 3 – Principles of system integration management used to the develop SI:D³ framework

Figure 4 – SI:D³ model for system integration

Figure 5 – Example of a physical system architecture view