Research Paper (postgraduate) from the year 2019 in the subject Business economics - Offline Marketing and Online Marketing, grade: 1,3, University of Mannheim (Chair of B2B Marketing, Sales & Pricing), language: English, abstract: Inter-firm relationships can occur simultaneously through multiple types of ties. For example, at the same time two firms might be supplier and customer, collaborate on R&D, have intertwined managerial and supervisory boards and compete for the same customers. This paper reviews and systemizes relevant academic literature on multiplex business relationships, identifies sources to collect data on multiplex business networks, and outlines future research directions.