<p>Complexity science offers valuable conceptual and analytical tools for addressing multifaceted socio-technical challenges in policymaking, promoting a holistic, dynamic, and adaptive framework that moves beyond traditional linear approaches. Despite its potential, complexity science has struggled to gain traction in the mainstream policy debates. This article examines the non-technical-human and organisational-barriers impeding the adoption of complexity science in policymaking and proposes strategies to overcome these obstacles. The barriers fall into three categories: management, institutional, and political challenges; communication and trust issues; and ethical considerations. The article synthesises insights from 37 interviews with complexity and policy experts to understand challenges and identify effective strategies. The findings reveal that entrenched governance structures, short-term political incentives, and limited awareness of complexity concepts among policymakers hinder the adoption of complexity-informed approaches. Additionally, a preference for simpler, more immediate solutions further obstructs the integration of complexity science into policymaking. Ethical considerations, such as data privacy and potential biases within models, also present significant challenges. Several strategies are identified to overcome these barriers, including fostering interdisciplinary collaboration, enhancing transparency in model development, and establishing experimental policy labs. The findings highlight the need for targeted training programs to equip policymakers with the skills to navigate complex systems and emphasise the importance of establishing platforms for interdisciplinary dialogue. These strategies aim to build capacity, improve understanding, foster trust, and encourage more adaptive and holistic policymaking approaches, ultimately facilitating the integration of complexity science into mainstream policymaking.</p>