In this chapter, we describe the measures required for professional onboarding, focusing in particular on the first working day and the three phases of onboarding. Since early and rapid integration of new employees into the team and the company is of particular importance at this stage, we examine in detail the differences between professional, social, and values-based integration. Furthermore, we describe the planning and implementation of so-called buddy concepts, as this form of close and personal support plays a particularly important role in onboarding from our perspective. In this context, we also provide a definitional distinction between the terms buddy, coach, and mentor. With regard to the topic of new work, we specifically address the question of integration and relationship-building with new employees who are engaged in remote or hybrid work. Finally, we provide best-practice examples, checklists, and examples for measuring onboarding success.