This article integrates Relationship Marketing (RM) and the Quintuple Helix Model (Q5HM) to examine how relational practices support collaboration within multi-actor innovation systems in Finnish Outdoor Education (OE). RM provides a framework for understanding value co-creation, trust, empathy, communication, and responsiveness as mechanisms shaping long-term cooperation, while the Q5HM conceptualises innovation as an interdependent process involving academia, industry, government, civil society, and the environment. The aim of the study was to examine the Finnish OE ecosystem through the complementary perspectives of Q5HM and RM, focusing on the organisation and interactions of key actors across the five helices and on the relational mechanisms supporting inter-organisational collaboration. A qualitative case study design was applied, drawing on strategic documents, national policy frameworks, official organisational materials, expert interviews, and field observations involving key actors in Finnish OE. Reflexive thematic analysis was used to identify RM-based mechanisms that shape inter-helix collaboration. The findings indicate that RM-related practices form an important relational dimension of the Q5HM, embedding trust, empathy, transparency, and shared learning into collaborative practices. These mechanisms support coordination across the five helices and contribute to both the continuity and further development of the OE network. The Finnish case demonstrateshow a relational perspective can deepen the understanding of Q5HM-based collaboration in sustainability-oriented educational innovation.