This master thesis explores the potential of Rhythmic Entrainment (RE) for product design applications. The research starts by defining some of the important terms and providing example cases of RE from products and research. A comparison between the cases illuminates the possibilities RE can have for product design and research. [1] RE can create interesting new product interactions, [2] the theory is not applied as broadly across industries. The second part of this thesis aims to collect and present the knowledge that is relevant to start designing with RE. A framework inspired by embodied interactions is presented, categorizing between human-product-context. The framework approaches designing with RE in an iterative manner, fostering simplicity while acknowledging the complexity of the design process. A product Benchmark test showed that being “hands on” can help designers understand the design tensions. These tensions are caused by the temporality of rhythm, the interaction between factors of the system and the particularity of cases. Interviews with experts in rhythm (by job, hobby or ability) showed how it can evoke strong emotions and create engaging experiences. The latter occurs when the full system interacts with each other, creating a loop of continuous feedback on the human rhythm, provided by the context or product. In literature, these symmetrical interactions with rhythm are considered valuable, but the practical knowledge and applications are not available. Therefore the last part determines the factors that influence different levels of responsive interactions from research. To test wether a more responsive interaction is preferable, a research through design case is executed with a design problem from Glimp. It wants to adjust its breathing rhythm to the user and guide it towards the goal rhythm of the exercise. This case resulted in a concept that applies a “configuration” level of responsiveness, while taking skill and data collection into account. The outcome of the research shows that a product can also be too responsive and that time influences sensor choices and the output. All of the results are summarized in the RE4Design framework that aims to inform designers about the topic in a visual and understandable manner.