ABSTRACT
Why do some changes to working practices appear to be irreversible, while others are abandoned? From its inception in 2001, the NHS Modernisation Agency encountered the ‘improvement evaporation effect’, as new working practices and increased performance levels were not maintained. One of the national initiatives affected was the booking programme (Chapters 6 and 7) where many of the gains of 1999 to 2000 had been ‘eroded’ by 2001 (Ham et al., 2003). But sustainability is not a new problem, having been famously described by Lewin (1951) as the need to ‘refreeze’ behaviour once change has taken place.
