Being very colourful and conspicious insects, dragonflies are well known to scientists as well as to nature lovers. Last century, several Belgian Odonatologists played a pioneering role in dragonfly systematics and distribution on a universal scale. Former distribution and abundance of this insect group is fairly well known in Belgium and Flanders. Our presentday dragonfly database is the result of intensive fieldwork carried out by volunteer cooperators of the Belgian Dragonfly Working Group GOMPHUS. For the whole of Flanders, more than 25.000 records are available, half of them collected during the last five years. They provide us a good picture of the actual species distribution and allow us to give clear judgements on rareness and population trends. In the first chapters we outline the overal goal and use of Red Lists, the collecting methods and the analysis of the data. 65 out of the 68 Belgian species have been observed in Flanders, 58 are since long autochtonous. For each species we compared actual presence (period 1990-1995) with former presence (1940-1965). We calculated for each period the percentage of sites (to the total number of all sites) in which the species occured and compared both figures to give us a measure for increase or decrease. We concluded that 9 species are “Extinct in Flanders”, 6 species are “Critically endangered”, 9 are “Endangered”, 5 are “Vulnerable”, 6 are “Susceptible” and 2 “Data deficient”. 21 species are categorized “Safe/Low risk”. The major part of the book consists of detailed species accounts, with information on distribution in Europe, former and present-day distribution in Flanders, important habitats, phenology, colonisation posibilities, main threats, management guidelines, completed with a list of useful references. In the last chapters, an overview of the most threatened dragonfly habitats in Flanders is given: rivers and brooks, oligotrophic waters (including bogs) and mesotrophic waters. Important threats and management guidlines are formulated. The positive ...