Neptune has promoted UK equity manager Holly Cassell in a bid to nurture "home-grown talent" at the firm.
Ms Cassell, who has served as assistant manager on Neptune's £604m UK Mid Cap and £24m UK Opportunities funds with Mark Martin, is to become deputy manager on the former and co-manager on the latter.
She joined the firm in 2013, having previously worked for Deloitte.
Neptune chief executive Robin Geffen said: "Holly’s contribution to the Neptune UK Mid Cap and UK Opportunities funds has been vital, and this promotion is recognition of that.
"At Neptune we pride ourselves in nurturing home-grown talent, and we have every confidence that Holly will excel in her new role.”