The composition of frog communities and the numbers of the various species present have been studied for over 15 years in several habitats in the Watagan Mountains are of New South Wales, making it possible to document changes in these features over this period. The habitats studied include two ponds, three streams, one site with both ponds and a stream, and several ephemeral situations. Fifteen myobatrachid and 15 hylid species occur in the area. During the period of the study five species have disappeared — three myobatrachids and two hylids. These are two species of Great Barred River frog (Mixophyes balbus and M. iteratus) that breed in streams; one pond species — the Green and Golden Bell Frog (Litoria aurea), and two species that breed in ephemeral situations, Bibron’s Toadlet (Pseudophryne bibroni) and an as yet undescribed species of tree frog. Although quantitative measures of abundance were not recorded over the entire period of the study, there was an apparent decline in the number of stream frogs, while the numbers of most species that breed in ponds and ephemeral situations appear to have remained unchanged. To understand the causes of the disappearances and declines there is a need to establish an active research programme involving experimental manipulations to eludicate the causes combined with the establishment of long-term monitoring sites and survey programmes.