The one activity that is common to all botanic gardens is the cultivation of plants. Many also have education, science, conservation, events and exhibitions programmes but cultivating plants is at the core of every botanic garden and plants are used to support all these activities. With existing and potential threats to plants and habitats it is essential that botanic gardens contribute to both the science and practice of plant conservation. This is because they have the staff skills and some of the resources required to make a significant contribution. However, if the live plant collections are to play a part in this work, and they must, then they must be guided by a Collection Policy and achieve the highest standards of sampling, record keeping and cultivation to make sure that the plants in question are fit for purpose. After describing the Collection Policy for the Royal Botanic Garden Edinburgh (RBGE) in Part 1, the paper covers the importance of wild origin material, targets, review and audits in driving up standards in Part 2. In Part 3, the inadequacy of some conservation collections are described. The approach taken by three different conservation programmes at RBGE which have embraced the need for rigorous standards in conservation collections are then described. These are the International Conifer Conservation Programme, the Scottish Plants Programme and RBGE’s Target 8 (of the Global Strategy for Plant Conservation) Project. Examples from RBGE’s Living Collection and Collection Policy are used throughout to illustrate the points being made.