The modular did not have to be invented: it can be found everywhere. We divide surfaces into grids, spaces into parts, and time into rhythmic units. Modular structures are also increasingly being recognized as a way of communicating, where the aim is not to construct a universal principle but to facilitate interplay between different systems. Building on the visionary design system that architect Fritz Haller and engineer Paul Scharer developed in 1965 for Swiss furniture company USM, 'Rethinking the modular' brings together specially commissioned essays and interviews with leading designers, architects and thinkers to present the wide-ranging importance and influence of modular design over the past fifty years. In revealing the broad possibilities created by balancing structure with flexibility, the timely publication redefines the place of modularity in modern design history, and offers a rich resource for designers today.