Mindful of the pressing need for housing, our laws and constitution deal leniently with squatters who take over other people's property. Once ensconced, the owner cannot evict them without providing alternative accommodation.

Enterprising scofflaws take advantage of this to organise invasions of land or buildings, cram the desperate into sardine-like conditions, then cream off "rent" for property they don't own or maintain. The result? An instant slum.

The legal requirement to provide alternative housing to evicted squatters lures thousands of desperate, homeless migrants and illegal immigrants to try their luck. The evicted jump the waiting list for homes and their new "landlords" skim off profits to everyone's disadvantage.

The sites soon run down and lose their value, which is what has entrapped municipalities such as Johannesburg and Cape Town in this scam.

Joburg wants to rebuild the squalid central business area as a world-class city, but can't do so until it displaces the thousands who have seized once-proud office blocks, transforming them into dangerous, foetid slums.

Tottering sewerage, water and electrical systems cannot cope with loads for which they were never designed, and the welfare of all their neighbours is put at risk.

These instant settlements serve no one's interests, including the settlers. It's time to reconsider how we enforce property rights and allocate housing to the poorest of the poor.