Hall joined Principal earlier this month in the role of project manager, following a 'significant growth' in business for the agency.
Other recent hires include Lidia Sakarapani, who joined the company in May as head of sales and marketing, Mark Throup, previously of First Event, who has been appointed as project manager, and Tabitha Law, who was hired as events coordinator.
Sakarapani was previously business development manager at IVORY Worldwide, and global partnerships and events manager for The World's 50 Best Restaurants Portfolio.
Anupa White, director of Principal, said: "In 2015 the team has really grown because our business has also continued to grow. We are very happy to announce the new appointments. Having the right people is important for us because we are like a family and all four new members have settled in well and become part of the Principal family."
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