Correspondence and papers concerning a summer school at MIT, 1963, on 'the Molecular Designing of Materials and Devices', at which Helen Megaw gave a paper on 'Competitive Structures and Phase Transitions'. File includes: correspondence with Arthur R von Hippel concerning participation and finalising of a paper for publication in a book to preserve 'the coherence of thought and sweep of broad horizons conveyed in our course'; ms of H M's original paper for the summer school; and typescript drafts of chapter for inclusion in the book, with illustrations.