This chapter will present some common techniques and design patterns that are used to implement modular applications with OSGi. It starts by introducing the concept of semantic versioning, which is a key part of how bundles and packages are versioned, followed by how baselining can be used to enable automatic version incrementing. This is then followed by an overview of some of the design patterns common in OSGi applications, including the benefits they present, and finally finishes with a list of best practices in OSGi.