Context: To analyze the effectiveness of adopting Behavior-Driven Development (BDD) with agile teams that have not previously used this framework. Problem: Lack of a study that combines guidelines inherent to adopting BDD. Solution: To achieve the proposed objective, the authors carried out two previous studies: the first identifying the state of the art of BDD through a Systematic Multivocal Literature Review; and, consequently, the state of the practice was analyzed, through a Survey, with professionals who use BDD in their work activities. Thus, this research sought to validate the guidelines found. Method: A case study was carried out in a private company focused on security software development with an agile team that did not use BDD. Summarization of results: The results obtained showed the effectiveness and validity of the guidelines previously found for adopting BDD. There is also a need for improving communication among stakeholders, the only problem found in BDD’s adoption. Contributions and impact: The main contribution of this study is the guidelines presented inherent to the adoption of BDD to contribute to both academia and industry regarding the understanding and implementation of this framework, respectively.