The paper discusses the history of the Hawksworth-Rose lichen scale (1970), which played a very important role in the development of bioindication studies and monitoring of atmospheric pollution in Europe. This scale was created to assess air pollution with sulfur dioxide in the period when its concentrations reached unprecedented values today. Due to the significant improvement in air quality and a clear decrease in SO2 concentrations in recent years (below the lower threshold of lichen sensitivity adopted in the scale, i.e. 30 µg/m3), further use of this tool (in accordance with the assumptions adopted by its authors) is not justified. The paper draws attention to the existence of other procedures for assessing the quality of atmospheric air (or more broadly – the environment), based on lichen diversity indicators (e.g. Lichen Diversity Value – LDV). Even though these tools do not allow for the identification of specific threats (both qualitatively and quantitatively), they seem to be as attractive and valuable as the lichen scale, and most importantly – they respond to the most current environmental problems. Keywords: lichens; bioindication; sulphur dioxide; species diversity; new approach methodology.