People who need robots are often not the same as people who can program them. This key observation in human-robot interaction (HRI) has lead to a number of challenges when developing robotic applications, since developers must understand the exact needs of end-users. Participatory Design (PD), the process of including stakeholders such as end users early in the robot design process, has been used with noteworthy success in HRI, but typically remains limited to the early phases of development. Resulting robot behaviors are often then hardcoded by engineers or utilized in Wizard-of-Oz (WoZ) systems that rarely achieve autonomy. End-User Programming (EUP), i.e., the research of tools allowing end users with limited computer knowledge to program systems, has been widely applied to the design of robot behaviors for interaction with humans, but these tools risk being used solely as research demonstrations only existing for the amount of time required for them to be evaluated and published. In the PD/EUP Workshop, we aim to facilitate mutual learning between these communities and to create communication opportunities that could help the larger HRI community work towards end-user personalized and adaptable interactions. Both PD and EUP will be key requirements if we want robots to be useful for wider society. From this workshop, we expect new collaboration opportunities to emerge and we aim to formalize new methodologies that integrate PD and EUP approaches.