We initiated research studies on the postharvest physiology of cut flowers almost 20 years ago, when the floriculture industry in Poland began to grow. At that time, like most flower growers in our country, we discovered cut flowers preserve their good appearance longer if kept in a vase with water rather than in dry storage. We then began intensive reading of various horticultural and other specialty journals, and we learned that many scientists had made the same dis­ covery long before and had gone even further, showing that sucrose and certain chemicals added to the vase water prolong the vase life of flowers much better than water alone. In the meantime, we learned that in the Netherlands, the United States, Israel, and elsewhere, great progress has been made in the postharvest treatment of flowers through the use of floral preserva­ tives; grading, packing, and transportation procedures; and the organization of trade. In all these countries, researchers generously offered their information to growers, wholesalers, florists, and indi­ vidual flower lovers eager to improve flower quality and keepability. We collected much of the practical information from various countries with the intention of using it in research projects con­ cerning the postharvest physiology of floricultural commodities.