A description is given of some of the demographic parameters for three populations of dandelions, one in an upland grassland (300 m) two in a lowland roadside verge (1 m). These latter populations differed in the density of dandelions found per square metre. All three populations were stable during the observational period, but differed greatly in the parameters that combined to give this stability. The chance of a seed producing seedling in the uplands was greater (x 23) than in the lowlands. The fecundity of plants in the lowland site was between 50 and 100 times greater than that in the uplands. Seed production in the lowlands was dominated by a few large plants. This was not the case in the uplands. The population turnover time was longest in the lowland high density site (20.5 years) and shortest in the upland site (15 years).