Drawing on guanxi and conservation of resources theory we explore how close personal ties between middle managers who participated in leadership development, constitutes an important social resource in an East Asian public sector context. We contribute to studies exploring the importance of informal leadership development opportunities and techniques, specifically utilised to overcome public sector structural barriers. We gathered qualitative data from 44 middle managers who had completed formal leadership development within the Hong Kong Civil Service. Our data revealed that high quality Superior‐to‐Subordinate Guanxi helped study participants to gain access to important development resources including further developmental opportunities, stretch assignments, developmental support and feedback. High quality Peer‐to‐Peer Guanxi helped them to gain access to peer tacit knowledge, participation in collaborative development projects and positive peer developmental feedback. Our findings inform future leadership development design and are relevant to East Asian public sector context's where guanxi ties are significant.