No / NHS maternity services in England must increase productivity if the NHS is to make efficiency savings by 2014. At the same time, it is expected to maintain or improve patient outcomes such as safety and quality. Given staff costs are 60% of the budget; it is likely that either the number or composition of the workforce will need to be changed to meet these targets. In this article, the authors argue that very little is known about the impact of altering the skill mix on either productivity or patient outcomes. Furthermore, it is unclear whether output and outcomes are themselves trade-offs between increased workload, increased number of deliveries and the increased complexity of demand.