Regulation 1829/2003, formally Regulation (EC) 1829/2003, harmonised the EU’s rules on genetically modified food and feed. It set up a single centralised authorisation procedure: any GM food or feed must be scientifically assessed, principally by EFSA, and approved by the Commission before sale. Crucially, it introduced mandatory labelling of GM ingredients, so that foods containing or produced from GMOs must declare it, giving consumers an informed choice regardless of whether modified DNA is detectable in the final product. The regulation works alongside rules on traceability and works in tandem with deliberate-release legislation for growing GM crops. It remains one of the strictest GM frameworks in the world and a frequent reference point in trade disputes.