18.41As well as contracting with private practice to deliver criminal defence work, the LAA also employs a small number of salaried lawyers in the Public Defender Service (PDS). This service was set up to benchmark the cost and quality of services provided by private practice and was never intended to be a nationwide scheme. At the time of writing, there are four PDS offices: Cheltenham, Darlington, Pontypridd and Swansea, and a national advocacy unit of employed advocates which accepts instructions from private practice.