The Open Learning Design Studio MOOC: Learning Design for a 21st Century Curriculum (http://www.olds.ac.uk/) was the first ever project-based MOOC on learning design. This ambitious MOOC ran for 9 weeks in early 2013. Its structure was based on a design inquiry model, where designers identify a (learning/curriculum) design challenge, explore it to gain an understanding of its context and driving forces, generate possible solutions, implement a solution and reflect on the process as a whole and its outputs. The MOOC exposed participants to a wide range of voices, approaches, representations, and tools for learning design. It incorporated a host of innovations in pedagogy and technology including Badges (http://www.olds.ac.uk/badges). Over 2000 people registered, over 1000 participated in the first week, and several hundred were active thoughout. OLDS MOOC adopted a radically open approach - registration was optional, and all the MOOC resources were made available as OERs. This session will reflect on what went well, what not so much, and what lessons can be learned.