Joining after an eight-year stint in financial comms and a further eight years in professional services, Lassalle is set to oversee the Church of England's comms department, working across traditional media, digital platforms and publishing.
Her background in commercial sectors echoes that of the current Archbishop of Canterbury Justin Welby, who spent 11 years working in the oil industry before moving into serving the church full-time.
Lassalle most recently worked as head of comms and marketing for Lloyd’s of London, and has also worked as head of communications at Actis, the private equity firm.
Before that, she worked at the global executive search firm Heidrick & Struggles, based in New York and in London.
Taking up the role on Monday (6 November), Lassalle is based at Church House, Westminster, with the comms department serving the Archbishops' Council, the Church Commissioners and the Church of England Pensions Board, as well as working closely with Lambeth and Bishopthorpe Palaces, bishops' offices, dioceses and cathedrals.
"The Church of England makes a unique contribution to the spiritual, cultural and social fabric of this country," she said.
"It's a great privilege to take up this position. I look forward to serving and enabling the life-changing vocation of the Church's diverse ministry and mission."
The Church of England is particularly keen for Lassalle to add to its digital and social media comms, and the Bishop of Norwich, Graham James, said: "I'm delighted to welcome Tashi to her new appointment.
"Her experience and imagination will be a huge asset to the Church of England in its task of proclaiming the gospel in an age of social media.
"She knows the scale of the challenge and I wish her well in all that lies ahead."
Meanwhile, William Nye, secretary general to the General Synod, added: "We are very glad to welcome Tashi Lassalle to the post of communications director for the Church of England's national institutions.
"She combines a personal commitment to the mission of the church, with wide professional experience in a range of sectors.
"She will help us build on the existing strengths of our communications effort across multiple channels, recently recognised in awards for our digital evangelism campaigns."
Lasalle replaces Arun Arora, who served in the role for five years until April, when he returned to ministry as a vicar at St Nicholas Church in Durham.
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