Conversely, living in the SE23 part of Crofton Park, it hadn't really occurred to me until I looked at the map that there were parts in SE4. I certainly don't think of us as living in Brockley.

Our personal affiliations are so much more organic than postcode or electoral boundaries drawn on a map.

Browsing around the SE23 postcode map it becomes clear that other wards spill into other postcodes. For example some of Perry Vale ward is actually SE26.

Of course one of the issues of living on the fringe is that you can be neglected by both sides since there is a tendency for funding to be allocated in the centre - this is probably more obvious at the borough boundary level since that is where most local service are delivered.

A recent case in point was the NHS "Picture of Health" consultation which assumes that this area affiliates itself with the NHS facilities to the south and east in Bexley, Bromley & Greenwich whereas most people I know who consider their local hospitals to be places to the west like Kings.