The 35mm filmstrip, which showed a series of still images often with an accompanying commentary, was one of the most versatile, popular and well-travelled media forms in the mid-20^th century, deployed in education, industry, by church groups and governments. Yet despite its widespread use – from rural communities in Scotland to government health campaigns across the British Empire – the filmstrip is often forgotten today, both by the archives that hold these materials and the scholars, educationalists and media practitioners that might use them. The Lost World of Filmstrips seeks to locate, uncover and examine this “lost” media form.”