The need for a collective work on the science of colloids formed a subject of discussion between the publishers of this work and myself shortly before the outbreak of the Second World War. The first preparations were brought to an end by the world events, in view of the fact that all possibility of contact with foreign colleagues had been broken. When the war continued year after year, the question arose whether we could restrict ourselves to Dutch collaborators and in 1944 I sent a request to a number of my fellow-countrymen to take this work m hand. It was immediately apparent that this plan was received with enthusiasm and most of those who now collaborate in this work met to devise a plan of campaign; a few others, whom we invited to do so, joined us later.
In our first discussion two points especially occupied our attention. In the first place the question was asked whether "colloid science" is an adequately definable concept. In the second place the question arose whether colloid science is a sufficiently homogeneous domain so that the work could be knit together by a general line of thought and would not degenerate into a collection of separate communications without inner coherence.