*CALL FOR WORKSHOPS* Continuing a long tradition, ER 2021 will host a number of workshops to be held in conjunction with the main ER 2021 conference. The workshops will serve as an intensive collaborative forum for exchanging innovative ideas about conceptual modeling, and for discovering new frontiers for its use. We specifically invite proposals for interactive workshops on new, emerging, or established topics in conceptual modeling, or its application in specific domains. We encourage workshop organizers to include activities that provide their participants with a true workshop experience. The conference and its workshops are expected to be hybrid, with both in-person and remote participation. Workshop proposals in any topics of interest to ER2021, are welcome. *IMPORTANT DATES* Proposal submission: February 7, 2021 Proposal notification: February 21, 2021 Workshop papers submission: June 16, 2021 Workshop papers notification: July 15, 2021 Final version of papers + summary of the workshop: July 31, 2021 Conference dates: October 18-21, 2021 *SUBMISSION GUIDELINES* Submission is done through EasyChair. Please select the Workshop track when submitting. Submission Link: https://easychair.org/conferences/?conf=er2021 Submissions must contain the following information: - Title - Duration (e.g. half a day, full day etc.) - Description of the topics and relevance of the workshop to ER community - Organizers (short CVs, limit of two pages each, experience in organizing events) - Proposed program committee - Expected numbers of submissions and participants including justification - Expected number of accepted papers - Format of the workshop including activities that facilitate discussion among participants, please explicitly refer to the expected hybrid nature of the workshop - Information about previous workshop editions (if applicable), including submission and registration numbers