11th Brazilian Congress on Metrology (Metrologia 2021) The Metrology 2021 congress was held from October 18th to 21st, 2021. It was a remote event, with all activities done in virtual rooms. The general president of Metrology 2021 was Americo Bernardes, president of the Brazilian Society of Metrology and professor at the Federal University of Ouro Preto.Metrology 2021 Magna session was the lecture Dr. Claire M. Saundry (NIST) gave on the first day, October 18th. Dr. Saundry spoke about the main activities of the Interamerican Metrology System (or “Sistema Interamericano de Metrologia” – SIM) regarding capacity building and knowledge transfer.Following the Magna session, on the morning of October 18th, the work began with the plenary lecture given by Dr. Daniel Varela Magalhães from the Mechanical Engineering Department at USP. The speaker gave a general outline of the new edition of the International Vocabulary of Metrology (VIM).Further after, on the afternoon of October 18th, two virtual rooms were held in parallel with the sessions related to CBM (general metrology) and CBMRI (ionizing radiations). CBMRI sessions also featured four thematic discussions on specific topics of interest.The second day of the congress, October 19th, started with the lecture of Dr. Thomas Hartung from the Johns Hopkins Bloomberg School of Public Health. He spoke about assessing the health effects of drugs and chemicals, which is considered a scientific revolution and a critical application of Metrology in the Health Area. Continuing in the Health area, Dr. Cameron Miller from NIST presented his lecture on documentary standards and the development of measurement methods for UV disinfection technologies. The plenary lectures were closed by Dr. Renato Garcia from UFSC, who spoke about quality programs in medical equipment used in primary health care, specifically about post-market safety and performance trials.Later, on the afternoon of October 19th, two virtual rooms were held in parallel sessions related to CBM (general metrology) and CBMO (optical metrology).The third day of the congress started with an exciting round table about female researchers’ presence in ionizing radiations. A plenary lecture by Stephane Solve from the “Bureau International de Poids et Mesures” (BIPM) Radiometry-Photometry group followed. The main subject was an extension of the BIPM on-site primary voltage standards comparisons to AC voltages, an important topic in Electrical Metrology. Further on, the morning works ended with a round table about Metrology in Health, featuring Renata Souza from FIOCRUZ and Roberto Macoto Ichinose from the Biomedical Engineering of COPPE/UFRJ.The afternoon of the third day started with two virtual rooms that held parallel sessions related to SEMETRO (electrical metrology) and to CIMMEC (mechanical metrology). Later on, there was another round table about Metrology in Health, specifically about metrological traceability of laboratory tests, with lectures by Dr. Marcelo Medeiros from INMETRO, Debora Michele Morone D’Aiuto from FIOCRUZ, Rafael Monsores from the company CONTROLLAB and MD Luisane Maria Falci Vieira, manager of the laboratory Álvaro Apoio.The event’s last day, October 21st, started with a plenary lecture by Dr. Jim Huggett from National Measurement Laboratory (NML), talking about the role of measurement science in supporting a molecular diagnosis of SARS-COV-2, a very current and hot topic. A vivid discussion on Metrology Education followed the plenary lecture.The afternoon of the last day started with two virtual rooms that held parallel sessions related to REMEQ (chemical metrology) and CBM (general metrology). Later, round tables were held in the two parallel virtual rooms, discussing hot topics such as metrological traceability, quality control on COVID-19 diagnostics, alternative methods applied to toxicology, and a web app developed for the performance evaluation of laboratories.Metrologia 2021 disclosed about 170 articles. After the second round of revision, the editorial committee selected the best 35 to be published by IOP JPCS.Metrology 2021 had sponsors from the industrial sector (Fluke Calibration and Sartorius do Brasil (Gold sponsors) and institutional support (ARBB Consultoria em Metrologia e Qualidade, RMMG, Canal Metrologia, REDE, SBLUZ and GM Metrologia). The event’s next edition will be face-to-face in 2023, from 28th to 30th November, in Itaipava, a gorgeous area belonging to the “Imperial City” of Petrópolis, Rio de Janeiro state. You are all welcome to join us! Rio de Janeiro, RJ, Brasil, August 28th, 2023. List of Editorial committee, Organizing committee are available in this Pdf.