The guidelines are divided into two parts: The first part makes general recommendations on how best to move germplasm of the crop concerned and mentions available intermediate quarantine facilities when relevant. The second part covers the important pests and diseases of quarantine concern. The information given on a particular pest or disease does not pretend to be exhaustive but concentrates on those aspects that are most relevant to quarantine. In general, references are only given on the geographical distribution of the diseases and pests. The present guidelines were developed at a meeting held in Wageningen, the Netherlands from 14 to 18 November 1988. The meeting was hosted by the Research Institute for Plant Protection and sponsored by the Directorate General for International Cooperation (DGIS) of the Netherlands Ministry for Development Cooperation.