This paper examines how the research capability of staff within New Zealand universities has evolved since the introduction in 2003 of the Performance-based Research Fund (PBRF). The analysis uses a database consisting of an anonymous ‘quality evaluation category’ (QEC) for each individual assessed in each of the three PBRF assessment rounds. Emphasis is on the evaluation of organisational changes in performance. The paper examines the extent to which each university’s Average Quality Score (AQS) changed as a result of changes in the QECs of existing staff over time and from the exit and entry of staff with different scores. The sensitivity of university rankings to the cardinal scale used by the PBRF is also considered and the degree of convergence amongst the universities is assessed. The data also include information about the age of staff evaluated in PBRF, and this is used to evaluate changes in the age distribution of staff across universities, and the ages of those making transitions within universities and between grades. The results reveal a systematic ageing of university staff in NZ and a significant change in the grade distribution by age, and age distribution by grade. A number of hypotheses regarding organisation change in response to the introduction of PBRF are discussed and tested by comparing universities with different patterns of change.