The articles in this special issue of Continuity and Change arose from a workshop held in Palma de Mallorca, Spain, between 9 and 11 September 1999, hosted by the Universitat de les Illes Balears. The workshop was called to celebrate the thirtieth anniversary of another conference, that held in Cambridge at the Faculty of History and at Trinity College in September 1969. It was this conference in 1969 that resulted in the publication of Household and family in past time: comparative studies in the size and structure of the domestic group over the last three centuries in England, France, Serbia, Japan and colonial North America, with further material from Western Europe, which itself has just celebrated its thirtieth anniversary. Household and family in past time (hereafter abbreviated to HFPT), in part largely due to the ‘analytic introduction on the history of the family’ contributed by Peter Laslett, subsequently became a seminal work in the field. It not only mapped out the methodological groundwork for the quantitative study of the historical co-resident domestic group, but perhaps unwittingly helped define a research agenda into comparative familial and social structural history that was followed for many years by Laslett, his colleagues at the Cambridge Group for the History of Population and Social Structure, and researchers from around the world. It became in a sense a manifesto, and one with which Peter Laslett personally was inexorably linked. Thus, with the sad death of Peter on 8 November 2001, this special issue of Continuity and Change took on a new double purpose: not only to mark the path-breaking 1969 conference and the subsequent publication of HFPT, but also to pay tribute to the remarkable life and work of Peter Laslett.