In modern day society concern is growing about the use of fossil fuels to meet our constantly rising energy demands, and the need for more sustainable energy is growing. Wind energy certainly has the potential to play a significant role in a sustainable future world energy supply and the wind power industry has grown to a globalized multi billion dollar industry. Manufacturers do not only compete with each other, but also with the traditional fossil energy sources. In order to come out on top, manufacturers are aiming at lowering the total turbine costs in order to lower the cost of renewable energy. An important way of achieving this is by reducing the total weight of turbine, by optimizing the design of each individual component. This causes a chain reaction of benefits as less material is used, transport and installation is made easier, a smaller foundation can be used and so on. On the downside, these optimized turbine designs generally introduce more flexibility to the structure. As a result, components start to exhibit local dynamic behavior, which can lead to increased component loading and decreased reliability. However, the aero-elastic models commonly used in wind turbine engineering are often incapable of predicting these local dynamic effects and their interaction with the global dynamics, due to their relatively few degrees of freedom and geometric simplifications. Therefore, a need exists for more detailed structural dynamic analysis tools, without losing generality and versatility. In this thesis the paradigm of dynamic substructuring is proposed to fill this need for detailed dynamic analysis tools in wind turbine engineering. Dynamic substructuring is a way to obtain the structural dynamic behavior of large and/or complex structures by dividing them into several smaller, simpler substructures (or components) of which the dynamic behavior is generally easier to determine. The dynamics of the total structure are then obtained by assembling the dynamic models of the components. A number of different techniques can be distinguished within the field of dynamic substructuring. In this thesis the emphasis is on the application and theory of Component Mode Synthesis techniques. The theoretical contributions are discussed first. Firstly, a general framework for substructure assembly is presented. In addition to the classic “primal” or “dual” assembly of interface displacements, this framework allows to assemble interface forces in a similar “primal” or “dual” manner. Furthermore, the framework enables the direct assembly of interface displacements and interface forces. The latter is called “mixed” assembly. In other words, direct assembly of stiffness matrices with flexibility matrices. Secondly, all common component model reduction techniques (Craig-Bampton, Rubin, etc.) and the relatively new Dual Craig-Bampton method are discussed. The Mixed Craig-Bampton method is introduced in this work and is a true generalization of the Craig-Bampton and Dual Craig-Bampton methods. It is shown that the accuracy of the Mixed Craig-Bampton methods is always in line with the Craig-Bampton and Dual Craig-Bampton methods, thereby emphasizing its versatility. Furthermore, a number of interface modeling strategies are discussed. Firstly, to enable assembly using only six degrees of freedom per interface, interface rigidification is discussed. A second option is to model the interface as fully flexible and retain all its degrees of freedom, which could result in incompatible substructure meshes. To overcome this issue several methods for assembly of non-conforming meshes are discussed. Finally, modeling of dynamic effects resulting from the interface itself (e.g. dynamic behavior of a bolt connection) is also presented in this thesis. Finally, interface reduction techniques are presented. Reduction of interface displacements is already well known from literature. On the other hand, reduction of interface forces, which is also presented in this work, has not been found in literature. It is shown that both methods are able to significantly reduce the number of degrees of freedom of the (reduced) substructure models. Using these methods and techniques, a dynamic substructuring analysis is performed using different reduced component models of the yaw system of a 2.3 Megawatt Siemens wind turbine. All the substructure components are modeled using the finite element method, but due to time limitations only one of the components is validated through measurements. By using the different component model reduction techniques, we were able to reduce the total number of degrees of freedom from almost 300.000 to approximately 750 for the entire yaw system, while maintaining an accurate model of the dynamic behavior for the frequency range of interest. From these results one can conclude that the dynamic substructuring approach shows great potential for use in wind turbine engineering. Even though some models are significantly simplified and not all the models used here are validated, it is clear that the techniques presented in this thesis allow for creating compact and accurate descriptions of the dynamic behavior of wind turbines. Nonetheless several challenges, with respect to non-linear models, controller models and others, are still to be met in order to generalize the methodology for application in wind turbine engineering.