Marshall is the co-founder of the RIghtshifting movement, and the creator of the Marshall Model (Dreyfus for the organisation), as well as Prod•gnosis, Emotioneering and FlowChain; the enterprise-wide approach to developing software-intensive products and services.

He has pioneered the application of psychology and psychotherapy techniques to software development, and these days, he most often works under the title of “Organisational Psychotherapist”.