Aim: The overall aim was to explore inter-organizational collaboration and adaptability in care coordination, focusing on seamless care for patients with complex care needs.

Methods: This thesis employed diverse qualitative methodologies across four studies. Studies I–III used an ethnographic approach with convergent data collection techniques, including document review, participant observations, and interviews with healthcare and social care professionals. Studies I and II applied the Functional Resonance Analysis Method to explore care transitions and identify vulnerabilities. Study III constructed a grounded theory of inter-organizational collaboration from insights across healthcare and social care domains. Study IV utilized a web-based questionnaire to collect written critical incidents reported by registered nurses in ambulance care. These incidents were analyzed using Critical Incident Technique and Interpretive Description, focusing on adaptation, decision-making, and learning in ambulance care during the COVID-19 pandemic. Lastly, findings from all studies were synthesized.

Findings: Seamless care for patients with complex needs depends on timing and precision in planning and information exchange across care provider boundaries. Gaps in these processes can increase vulnerabilities (I, II). Effective care coordination relies on bridging professional and organizational divides through established collaboration pathways while stretching across organizational boundaries, rather than dissolving them (III). Continuous learning is central, leveraging lessons learned from adaptations made under pressure to foster resilience and ensure effective care delivery (IV). Coordinating care in organizational borderlands—the spaces where professional roles and organizational boundaries intersect—requires continuous communication, negotiation, and shared decisionmaking. Adaptability enables healthcare professionals to navigate the complexities of real-world care and bridge the gap between protocols and practice by balancing standardized procedures with context-specific, flexible decision-making.

Conclusion: Well-defined boundaries, established collaboration pathways, and adaptability are necessary to overcome challenges in fragmented healthcare systems. When maintained with flexibility, boundaries facilitate coordination by defining roles and responsibilities while still allowing healthcare professionals to adapt to emerging situations. Rather than needing to be dissolved, boundaries provide a structure that reduces ambiguity and supports effective collaboration. Striking a balance between stability and adaptability is, therefore, essential for achieving seamless care for patients with complex care needs.