The discipline of software testing is increasingly drawing industry's attention to itself due to the demand for quality products and the high level of competition in the market. This scenario can be supported by a maturity model that continuously improves the discipline of testing when applied to the software development lifecycle. Therefore, MPT.BR, the acronym in Portuguese for Improving Test Processing. Brazil, is presented as a maturity model for testing to help when introducing testing disciplines in software organizations. It can be seen as an alternative for companies that aim to increase their product quality and ROI. MPT.BR has been applied over the last 3 years in small and medium-sized software organizations, the results of which will be discussed in this paper.