This paper reports on the development of an innovative semi-quantitative assessment method to estimate the level of uptake of cleaner production (CP) in small to medium-sized enterprises (SMEs) on the basis of three component ratings: awareness of CP ideas and benefits; presence of management features and/or system components conducive to CP; and CP content of recent innovations and operational improvements. The assessment method was designed for application through a telephone survey and was deliberately structured to minimise intentional socially preferable responses. It was trialled on 140 SMEs in four sectors, mostly from Western Australia: printing and book making; dry-cleaning; food processing and metal products. The trial showed that the assessment tool can judge the business’ capacity to implement CP. The levels of CP uptake found in the trial reflect well on the experience of CP practitioners, albeit much lower than reported from previous mail surveys. In the trial the drycleaners performed significantly better than the other businesses, with food processing, metal processing and printing businesses being ranked second, third, and fourth respectively. The higher uptake by drycleaners was expected given that a sector specific CP program was conducted in that sector. Overall, the results suggest that generic (non-industry specific) semi-quantitative proxy indicators can be used for estimating the level of CP uptake in SMEs. Although further verification with quantitative environmental and economic performance data would in principle be desirable, this would be impractical due to the general lack of monitoring and recordkeeping of environmental data in many SMEs, and would also face the common conceptual, methodological and fundamental challenges for CP quantification. The tool may therefore be more useful to target CP promotion efforts, and measure their effectiveness.