The Government says new grocery rules will stop the abuse of power by the country's supermarket duopoly.
Foodstuffs and Woolworths will no longer be able to decide when to pay suppliers, reject fresh produce or force suppliers to pay for promotion of their products.
They could be slapped with millions of dollars in fines if they don't comply.
Reporter Niva Chittock and visual journalist Nate McKinnon were at the announcement in Canterbury today.