Performance measurement in the English public sector has been implemented in a top-down manner. The mechanics of this regime (centralised targets, public reporting of performance data and the use of rewards and penalties) are driven by central government and are intended to hold agencies to account for their performance and regulate their behaviour. This paper examines whether the operation of such a regime has resulted in the improved performance of social care organisations. Comparable data from Northern Ireland Health and Social Services Trusts, where performance measurement processes are less centrally driven and rewards and penalties are less contingent on ratings, are used to investigate the potential impact of different performance regimes. Indicators of admissions to residential care and delayed discharges from hospital are used to signal progress in the meeting of social care objectives in the two countries.We find that in England social care organisations have broadly improved their performance over time in composite ('star') ratings and with generally higher ratings across individual indicators, with noteworthy improvement across key threshold indicators (measures which councils must perform well on to obtain a good summary rating). The comparative analysis highlights the differences across the two countries with an improvement in performance over time in England and a fairly static picture in Northern Ireland. These improvements may reflect a host of factors other than the incentives created by centralised targets and measures. Our data show, for example, that external characteristics of English councils predominantly influence their being reported as 'poor performers'.Evidence suggests that the rate of performance improvement reflects the incentives inherent in the English performance system. An incentive structure that promotes the 3 achievement of specific targets may have influenced the behaviour of local managers responsible for performance in this sector. However, further information from local organisations is required to more fully explicate all the relevant factors that may have a bearing on reported performance. The evidence reported here does, however, point to the beneficial effects (at least for the regulator) of centrally set measures. It is uncertain whether more recent moves away from this target regime in England, towards the development of local indicators and 'individual incentive' regulation, will likewise offer the appropriate inducements for performance improvement.