The Citizen-Enhanced Open Science in Southeastern Europe (The CeOS project) set out to raise awareness and promote best practices in Southeast European countries (BG, CY, EL, HR, IT, RS) that lag in open science (OS) and citizen science (CS) and are lowly involved in developments like the European Open Science Cloud (EOSC). The project monitored OS and CS implementation, documented best practices in a fair manner, and engaged non-expert groups in social participation.