We have the pleasure of welcoming you to the next edition of the Conference on Complex Systems CCS2023 in Salvador da Bahia, Brazil. The CCS is the largest and most important annual meeting of the international complex systems community. It comes under the auspices of the Complex Systems Society. This edition, organized by SENAI CIMATEC, takes place after previous events hold in, Mallorca, Lyon, Singapore, Thessaloniki and Cancun.