More and more product development projects face Volatile, Uncertain, Complex and Ambiguous (VUCA) conditions that challenge the companys competitveness. This is why an appropriate product development method is crucial to support the project team to successfully achieve an innovative and marketable product, that can yield the intended return on investment. Agile development, which in particular has been shaped and became prominent in the software industry, adapts to changes quickly and strives to utilize them in ones own favor. However, agile methods are designed for virtual (software) products. Using them for physical (hardware) products in Mechatronics, which involves materialization, is not trivial due to the so called Constraints of Physicality (CoP). If agile development was applicable in Mechatronics, it would be easier for companies to increase their competitiveness under VUCA conditions. With this motivation in mind, the investigation answers the question on how to cope with the CoP in order to organize mechatronic product development projects in an agile manner. New solution approaches in form of a framework are derived. While many existing agile methods suffer from the guru problem (i.e., founding fathers postulate their methods, but lack a thorough explanation on why they work), the framework is well-grounded in theory. To achieve that, the lead user method was carried out to identify and learn from cutting-edge users of agile methods in Mechatronics. Moreover, a review of the scientific literature was conducted to enrich the solution space. As a result, the framework contains ten agile principles and three agile practices. Appropriate pirtyping, situation-specific evaluator selection and value-based modularization are key takeaways.