In the latter, one office is often given more significant administrative responsibilities and a co-ordinating role. In less urban areas, these responsibilities are more frequently found at a sub-regional level OECD (2009a). This department operates a district office in the Brunei-Muara district (with a population of roughly 200 000). As the total population of Brunei is only 388 190 (equivalent to the sub-regional level in other countries) the PES was considered to have maximum flexibility for the purposes of this study.