As part of the activity related to atomic and nuclear decay data evaluations, the French national metrology laboratory for ionising radiation, the Laboratoire National Henri Becquerel (LNE-LNHB), coordinates the Decay Data Evaluation Project (DDEP). The DDEP is an international collaboration providing easy-to-use and reliable decay data recommendations. It was originally founded in 1994 between two National Metrology Institutes (NMIs) for ionising radiation: the LNE-LNHB, France, and the Physikalisch-Technische Bundesanstalt (PTB) in Germany. The collaboration was later strengthened through the addition of laboratories from the US, China, Romania, Russia, Spain and the UK. Beyond the initial scope of ionising radiation metrology, the DDEP recommendations are used for a wide variety of topics, from fundamental physics to nuclear medicine applications. Most notably, almost all 220 DDEP evaluations are included in the latest version of the radioactive decay data library from the Joint Evaluated Fission and Fusion (JEFF) file project of the OECD Nuclear Energy Agency. This communication aims to present an overview of the evaluation project. The guidelines of the collaboration as well as the evaluation pipeline will be presented. The various dissemination media used by the collaboration will be detailed and the recent update of the website will be highlighted. The future improvements of the database will be discussed.