The sustainability problems in cocoa

Low farmer income is the root. A household that cannot afford hired labour uses household labour, which is where a large part of the child labour picture comes from. A household that cannot afford to replant ageing trees extends into forest instead, because clearing new land is cheaper than waiting five years for replacements to bear. And a household with no financial buffer cannot adapt to a changing climate.

Treating the four as separate campaigns is how interventions end up working against each other — a deforestation control that reduces farm area without addressing income increases the pressure that caused the clearing.

Two countries grow more than half the world's cocoa. That means a disease outbreak, a weather event or a policy change in West Africa is a global supply problem with no region large enough to absorb it.

Cacao swollen shoot virus has caused sustained losses and has no treatment once a tree is infected; control means removing trees. Much of the West African tree stock is ageing and past peak productivity. And climate projections suggest suitability will decline in parts of the current growing area, which is a slow problem that a perennial crop is badly placed to answer.

Certification, which pays a premium to producer organisations against an audited standard. Direct trade, which pays a negotiated price with no audit. Living income pricing, including origin-country mechanisms imposed by producing governments rather than by consumers. Corporate sustainability programmes. And, most recently, regulation placing due-diligence obligations on importers.

They are different mechanisms with different leverage and different evidence behind them, and the honest summary is that none has yet closed the income gap at scale.