Just about to head off to spend an afternoon with folk particularly interested in behaviour change.
Thought I'd share these few brief thoughts about the existing models
1. most start from the assumption that the individual is the right level of granulation for studying behavior (and thus behaviour change). Fine, if we were a solitary species of independent agents but (as we argue here regularly) this doesn't appear to be a good characterisation of Homo sapiens. We are a social species - more so that most of our relatives - and we do what we do in the company and under the influence of others (real or imagined). Most of human life is - as Oscar put it - a quotation from the lives of others.
2. most of the fancy models touted aren't behaviour change models at all but rather "how to change people's behaviour" models: in other words they presume that change is something generated largely by external ("exogenous") forces and (hate the word) "levers".
3. as a result most ignore the changes in behaviour that arise without external interventions (such as marketing), assuming that this cannot amount to much. Yet these changes are happening all the time in all aspects of our lives.
4. Few admit the enormous failure rate of attempts to change people's behaviour - in marketing, in public policy, in (change) management and in our daily lives. It's really hard to set out to change behaviour - far better to help the behaviour change itself, don't you think?