Effectiveness of the Mobile Field Study Unit's work in environmental education in south-west Queensland during 1979-1980 was evaluated through records kept by the Unit and the Priority Country Area Program (PCAP) office, evaluations by teachers, interviews with teachers and educational administrators, and participant observation of the Unit. The Unit was one of a number of initiatives sponsored by PCAP in an effort to bring more varied experiences to country children in "disadvantaged country areas." During 1979-1980 the Unit provided service to some 1,400 pupils, 75 teachers, and 35 schools each year, at a cost of approximately $90,000 per annum. The majority of informants judged that the Unit had provided a valuable service and that its efforts were well received. In relation to field study facilities, disadvantage previously experienced by the area's children had been effectively overcome. The Unit had been more successful in contributing to the environmental education of pupils than in influencing teachers to make greater use of environmental strategies. In the interests of cost-effectiveness, a reduction in Unit staff will be trialled during 1981, together with plans for increasing the responsibilities of visiting teachers and some decrease in Unit mobility. These changes will need to be carefully monitored. (Author/BRR)