This workshop brings together leading scientists to tackle one of the most pressing challenges in modern proteomics: ensuring the trustworthiness of peptide and protein identifications through robust false discovery rate (FDR) estimation. As mass spectrometry data grows in complexity—especially with advances like data-independent acquisition and deep learning tools — existing FDR methods face critical limitations. Through in-depth discussions, collaborative breakout sessions, and hands-on exploration, participants will investigate and improve the assumptions, tools, and practices underlying FDR control, shaping the future of reliable, reproducible proteomics research.