The first versions of Kaplan and Norton's interpretation of the balanced scorecard asserted that relevance should derive from the corporate strategy, and proposed design methods that focused on choosing measures and targets associated with the main activities required to implement the strategy. As the initial audience for this were the readers of the Harvard Business Review, the proposal was translated into a form that made sense to a typical reader of that journal – managers of US commercial businesses. Accordingly, initial designs were encouraged to measure three categories of non-financial measure in addition to financial outputs – those of "customer," "internal business processes" and "learning and growth. " These categories were not so relevant to public sector or non-profit organisations, or units within complex organizations (which might have high degrees of internal specialization), and much of the early literature on balanced scorecard focused on suggestions of alternative 'perspectives' that might have more relevance to these groups(e. g. Butler et al. (1997), Ahn (2001), Elefalke (2001), Brignall (2002), Irwin (2002), Radnor et al. (2003) ).