KP is the standard trade abbreviation for the Kimberley Process, the inter-governmental certification scheme adopted in 2003 to prevent rough conflict diamonds from entering the legitimate international supply chain. The full title is the Kimberley Process Certification Scheme, abbreviated KPCS; in conversation, correspondence and shipping documents, dealers commonly contract this further to KP.

The scheme was negotiated through United Nations resolutions and meetings convened in Kimberley, South Africa, from May 2000, and entered force on 1 January 2003. It requires participating states to certify each export shipment of rough diamonds with a tamper-resistant document confirming that the parcel is conflict-free, and to refuse imports of rough diamonds from non-participants. As of the mid-2020s, the KP has more than 80 participating governments representing the European Union and most major producing, trading and cutting countries.

For working jewellers and dealers, KP touches the rough trade rather than polished goods, but its language has migrated into customer conversations. Polished diamonds are accompanied by a separate written warranty, the System of Warranties developed by the World Diamond Council, which carries the KP guarantee through each transfer of cut stones. Reform debates within the scheme are tracked under the term KP reform, while its civil society participation is organised under the KP Civil Society Coalition.