Who are CST

We are dedicated network of firms who
deliver expert tax and accounting advice to
private clients in major global centres.


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CST Tax Advisors was established in the U.S. in 2010 as a network of independent affiliated accounting firms providing specialist U.S. tax and accounting advice to global private clients and international enterprises doing business in the U.S. With offices in major U.S. cities our specialist tax advisors and CPA’s provide global private clients and international enterprises with broad cross border tax and accounting compliance issues. Our links with our members of the CST Tax Advisors group in Europe, Asia and Australia provide us with the ability to provide robust and integrated tax advice to our clients. As the only dedicated CPA firm servicing the needs of citizens of Expatland we are able to provide unique insights to our clients both within and outside of the U.S.

Our Mission Statement

CST Tax Advisors aims to provide private clients and international private enterprises in Expatland with integrated tax and accounting advice for both their home country and the country in which they operate.


Our member firms are located in major international cities and we are therefore able to directly service our global clients in Expatland.

Our professional contacts mean that many cross-border business matters can easily be addressed. Our professional affiliations and professional relationships allow us to co-ordinate a solution to whatever professional tax or legal issue a client may have. This reduces many of the communication difficulties when an expatriate or business person is considering an international move.
To learn more about Expatland click here.

The History of CST

CST Tax Advisors was founded in 1992, by John Marcarian in Sydney, Australia. From the early days of the Firm it was recognised that the private client tax market for Australian expatriates and international businesses was unique market segment. The United States proved to be a very popular destination for Australian expatriates and entrepreneurs given the close relationship of Australia and the United States. As a result CST Tax Advisors was established in 2010 with Peter Harper being appointed as Managing Director of CST Tax Advisors North America. CST Tax Advisors now operates from multiple locations in the United States and is growing strongly in the U.S Market. In addition to our U.S. offices, CST Tax Advisors now has international offices in London, Sydney, Hong Kong, Singapore and Tel Aviv.

John Marcarian

As John says

As John says

The beginning of the CST way was grounded in delivering quality services to the executive, private client or family business. I always believed that the relationship with the client was the foundation stone of the Firm and our obligation to maintain that relationship meant that we were not to be just about the chargeable hour and answering questions – but rather is a sense of obligation to go the extra mile to think about things that we ourselves would want done – if we were the client.

Our Key Value Proposition is to continue to provide expat individuals and international enterprises in ‘Expatland’ with integrated tax accounting and structuring advice for both their home markets and the international markets in which they operate. We do this by having empathy to their facts and circumstances and focussing on executing tax and business solutions.

We strongly believe that by focussing on clients living and working in ‘Expatland’ we can deliver on the above statement through our global brand and our united delivery platform.