Donald Schön an American philosopher, author, and Professor at Massachusetts Institute of Technology, produced a series of books on learning, Reflective Practice, and significantly, the development of reflective practitioners.

Schön distinguishes between reflection-in-action and reflection-on-action.

Reflection-in-action is reflection during the ‘doing’ stage. It allows one to deal with surprising incidents that may happen in a learning environment, encouraging responsibility and resource, and the drawing on one’s own knowledge partly so as to apply it to new experiences. It allows for personalised learning as – rather than using preconceived ideas about what should be done in a particular situation – one decides what works best at that time for that unique experience. Reflection-on-action involves reflecting on how practice can be developed after the lesson has been taught. Schön recognises the importance of reflecting back ‘in order to discover how our knowing-in-action may have contributed to an unexpected outcome’. Reflection-on-action means to reflect after the event on how knowledge may direct one to the experience one had. Reflection-on-action should encourage ideas on what needs to be change in future.

His seminal work ‘The Reflective Practitioner‘ (1983) focused on professional Reflective Practice and the role of the reflective practitioner. In his model, learning to reflect in action (RIA) and look back on action (ROA) together form a reflective process for decision-making and professional growth. Experiencing surprise or uncertainty during reflection in action could be described as ‘light bulb’ moments, as in Köhler’s earlier insight studies.