This research examines the factors influencing pro-environmental behaviour adoption in Estonianmanufacturing SMEs and explores how Systems Oriented Service Design (SOSD) can facilitatethis transition. Most Estonian manufacturing SMEs fall outside the scope of the CorporateSustainability Reporting Directive (CSRD), leaving their environmental behaviour largelyunregulated, and the study is grounded in Value-Belief-Norm (VBN) theory and the leveragepoints framework to address this gap. Data were collected through an observational field visit toan Estonian PVC hall manufacturer, semi-structured interviews with four sustainability expertsand four members of the case organisation, and a participatory workshop with six service designpractitioners. The research finds that organisational attitude is the root barrier topro-environmental adoption, preceding and causing gaps in knowledge, capability, and practice.In response, the Pro-environmental Behaviour Toolkit was developed — a four-step facilitationresource designed to equip service designers to promote pro-environmental behaviour withinmanufacturing SMEs.