This paper reports a study on the cleaner production program developed in the plastic industry in São Paulo - Brazil. An evaluation model was developed, using as reference the existing literature on business models and process management, as well as excellence models adopted by national quality awards from different countries. The model was applied for in-depth multiple case study in eight plastic companies to validate the importance of management processes in the implementation of cleaner production programs and to observe the results obtained with the cleaner production initiatives. The research has identified two companies with more than 92% compliance to the model which reached important environmental results in the last three years. The results are supplemented with the use of external performance indicators (material intensity, water and carbon footprint savings) to show that little changes inside the companies can reduce upstream impacts and bring greater benefits to the environment.