Abstract: For decades, migration to Germany has been a relevant social phenomenon resulting in an increasing share of foreigners and Germans with migration background in the German populace. Additionally, since 2015, Germany has experienced a substantial increase in the immigration of people seeking refuge and asylum from civil war, economic and environmental catastrophes, and other adverse living conditions. These developments can be assumed to have led to an increase in intergroup contact between Germans and foreigners. We investigate this phenomenon in a multifaceted fashion by combining a social indicator and monitoring approach using repeated cross-sections over time with a new panel approach using a short-time panel to study causal relations. As a first step, we descriptively analyze the development of intergroup contact experiences of the German population with foreigners in various areas of life using data from the ALLBUS survey collected over 36 years between 1980 and 2016. Specifically, we detail the diverging contact experiences of participants with and without migration background as well as participants in the former Eastern and Western part of Germany. In a second step, based on Allport’s intergroup contact theory that contact with outgroup members may improve attitudes towards these outgroups and other related findings, we examine the longitudinal processes between positive intergroup contact with foreigners and attitudes towards foreigners using four waves of the GESIS Panel collected over approximately one and a half years. We apply special rigor to these analyses by differentiating stable differences in intergroup contact experiences and attitudes between participants from within-person processes and discussing the implications of this differentiation.