Jan has been the Principal of Somerville College since 2017 and during this time has attracted more than £40m of investment to Somerville College.

Jan has deepened Somerville's unique Oxford-India partnership including a recent £12m agreement with the Tata Group to construct a new flagship building at Somerville College. Her work with India has enabled her to create a pipeline of future policy makers, environmentalists and progressive advocates for India and the global south including The Savitribai Phule Scholarship – first UK scholarship for traditionally marginalised Dalit/Adivaasi students and The Cyril Shroff Scholarships focusing on policy makers, environmental change-makers. Jan also helped to establish the OpenAg symposium on sustainable agriculture.

She also oversaw an expansion of scholarship provision at Somerville College and initiated outreach to local primary schools. Royall served as Chair of Conference of Colleges from 2020-23, and for two years prior as Deputy Chair. In 2021, Royall led a campaign for Somerville to become a College of Sanctuary, offering a pathway to Oxford for students displaced by war or internal unrest. The University of Oxford has now adopted this campaign, forming a Community of Sanctuary

Prior to becoming Principal of Somerville College, Jan served as Chief Whip in the House of Lords and then Leader of the House. During her leadership, Jan steered through the 2010 Equality Act, which legally protects people from workplace discrimination and wider society. Janet also successfully blocked the sale of UK public forests and campaigned for tougher sentencing for people convicted of stalking offences, including the successful tabling of an amendment to the bill on stalking in 2022.