The International Centre for Regional Planning and Development (ICRPD) was conceived at a joint symposium held in London in 1953 , organised by the School of Planning and Research for Regional Development, the School of Planning Club and Community Development Projects Ltd. At the symposium it was agreed that a centre for research and education, which would provide an information service and a meeting place, was required to enable closer contacts between the professions concerned with regional planning and development.
A preparatory Committee was elected, which went on to organise the International Conference on Regional Planning and Development held at Bedford College, London in 1955 . At this conference the resolution was passed to investigate setting up such a centre. GE Janson-Smith from the United Kingdom was elected chair of the international Provisional Committee charged with the investigation.
Percy Johnson-Marshall was elected one of the British members. This Committee, through a number of meetings, developed a constitution for the proposed centre, which was finally approved in November 1957 . An International Seminar, which studied the history and concepts of regional planning, was held in The Hague, by the Netherlands Universities Foundation for International Cooperation, on behalf of the ICRPD in July 1958 . At this conference practical goals and membership criteria of the ICRPD were established, the focus having moved from the establishment of a physical centre to a dispersed programme of professional support and international collaboration. The ICRPD would aim to: document and diffuse information, undertake research, hold meetings, educate, create a register of experts and consultants and undertake public relations.
In 1958 the ICRPD exhibited at the World Exhibition in Brussels.
International relations began to sour when it became apparent that a lack of financial support from the United Kingdom government, amongst accusations of communist sympathies, meant that the centre of activities would likely be established in the Netherlands. At this stage the British Group of the ICRPD, chaired by Robert Joseph Gardner-Medwin became more active. It had its own General Council, on which Percy Johnson-Marshall sat, and arranged study days for its members. These included the titles 'Economic forces leading to urban concentration' and 'Urbanisation in the tropics - its causes and methods of control'.
Plans for an ICRPD Conference in Rhodes in April 1963 were strongly contested by the British Group, leading to the resignation of the president Leo Brandt.