In certain circumstances the ABS system on Toyota's Prius gives too much kickback through the brake pedal.
Drivers tend to think this means braking action is delayed. It isn't - if they don't lift their foot they'll find the brakes work as normal.
But a software update to the affected cars will change the feedback and drivers should find braking feels 'normal.' It affects only the Mk3 Prius, and only the first few months' production.
Find out if your car is affected, by contacting your deal - find your local dealer here