Mar Meelis Zaia, is the Assyrian Church of the East's Metropolitan of Australia and New Zealand. He was ordained a priest of the Church in 1982 in California. He was appointed Bishop of the Church’s diocese of Australia and New Zealand in 1984 and arrived to take up that position in March 1985, which he held until 2008 when he was elevated to His Beautitude Mar Meelis Zaia, Metropolitan of Australia and New Zealand.
He is the chairman of the Board of Trustees which controls the financial affairs of the Church. Since his arrival, as head of the Church he has steadily built up the diocese in Australia. His duties include fundraising, active pastoral work, and arranging for the purchase of property and the construction of buildings when required. In 1990 he played a central role in obtaining a donation of $1.1 million to build a cathedral in Greenfield Park, and in 1999 assisted in the raising of funds for the construction of a reception hall on the cathedral property. In recent times, he played an important part in raising funds from private and government sources for the construction of classrooms and an administration facility for a primary school.
His Beautitude's diocese includes all of Australia, including Sydney and Melbourne, and New Zealand. He said that there are about 19,000 registered adult members who contribute financially to the Church, and about 4,500 registered non-paying members under the age of 18 years. Of the adult members there are approximately 13,000 in Sydney/New South Wales, 3,500 in Victoria, and 2,500 in New Zealand. The Assyrian community also includes about 6,000 people who are not members of the diocese.
As Bishop, His Grace Mar Meelis Zaia was honoured by the Queen of Australia Her Majesty Queen Elizabeth II on the January 26, 2007 in the Australia Day Honours List and was awarded an Order of Australia (AM) medal for his community service through the Assyrian Church of the East and for his pioneering work in the field of education and the establishment of educational facilities. 
His Beautitude Mar Meelis Zaia is also viewed by many in the Assyrian community in Australia and abroad as one of the pioneers of the Assyrian Church of the East in Australia, by expanding and contributing to the growth of the church and its activities. The establishment of the first Assyrian school outside of the Assyrian homeland (Mesopotamia), St. Hurmizd Assyrian Primary School in Sydney was a fulfillment of His Beautitude's vision. Mar Narsai Assyrain College, a secondary school in Sydney, is now the second school run by the Diocese of Australia and New Zealand, catering to hundreds of student in the Fairfield area and its surrounding suburbs. In 1988, as Bishop His Grace officially established the Assyrian Church Youth Group, focussing on the teaching and preaching the word of God in Assyrian, which is until present day active within the community.
In 2004 as Bishop His Grace Mar Meelis Zaia also approved and supported the establishment of the St. Peter and Paul Parish in Sydney; an English-speaking parish created to work for the benefit of Assyrian youth. The fledgling parish has grown from only 50 members to a 300+ strong congregation in less than two years. His Grace has also initiated a number of programs for troubled youth including drug and alcohol addicts.
On the 7th of December 2008 His Grace Mar Meelis Zaia became His Beautitude Mar Meelis Zaia, when he was elevated to the rank of Metropolitan of Australia and New Zealand. In this spectacular event he was blessed by His Holiness Mar Dinkha IV who flew from Chicago along with a further five bishops from around the world.
The event draw close to 3700 people on a raining morning at the St Hurmizd Assyrian cathedral, Greenfield Park in Sydney Australia.