As well as locally, she works at national and international level.
As Education Officer of the Civic Trust she and colleagues at the National Trust and English Heritage worked to ensure that education in, about and for the built environment was a key part in the first draft of the National Curriculum. With colleagues in the Civic Trust's Regeneration Unit she encouraged young people and local communities to take an active part in reshaping their neighbourhoods. She edited Shaping Place, a national environmental education broadsheet for teachers. She and colleagues at the National Trust and English Heritage worked to ensure that education in, about and for the built environment was a key part in the first draft of the National Curriculum.
Celia Clark taught University of Portsmouth Restoration and Decorative Studies students the history of architecture and building conservation from 1989 until 2008 when the course closed. The Omega Centre where she taught latterly is where she practices ceramics with Portsmouth Makers. This 1880s Board School currently belongs to the Portsmouth Elementary Education Trust, whose trustees are all city councillors. It is a thriving arts, sports and literacy hub. Celia is working with the Omega Centre Users' Group to secure its future. She has saved many Portsmouth buildings from demolition, finding new creative life for them.