Board assurance: What do we know? How do we know we know it? (25 February 2026)

Summary

In NHS boardrooms, the word assurance is used constantly, but beneath it lies the far deeper question of “how do we know what we think we know?”

Over three years as a non‑executive director (NED) and committee chair, C J Harrison increasingly felt that the debates about assurance are really debates about knowledge. Its sources, limits, trustworthiness, and blind spots.

Board Assurance Frameworks aren’t just governance tools. Their use reveals the underlying philosophy and the theory of knowledge by which organisations understand themselves.

This article explores the epistemology (understanding of knowledge) on which NHS board assurance is based, why it matters, and how NEDs might use these insights to improve scrutiny, decision‑making, and organisational learning.

While the article focuses on the distinctive responsibilities of NEDs, these responsibilities sit firmly within the unitary board model, in which executives and non‑executives are collectively responsible for decisions, collectively accountable, and collectively dependent on the quality and reliability of the knowledge available to the board.