Qays is a licensed litigator and is an arbitrator of the GCC Commercial Arbitration Centre and a licensed lawyer and legal consultant in Bahrain and in Dubai, UAE. Qays joined the law offices of Hatim S. Zu'bi & Partners in Bahrain in 1981, and went on to become a Partner.

In the early 1990s, through the firm, he entered into an agreement with the leading Canadian law firm of Stikeman Elliott to jointly pursue legal opportunities in the Middle East. Thereafter, Qays joined Al Futtaim & Sons, a major trading house in Dubai, as legal and business development advisor to the Chairman, whereby he gained vast experience and knowledge in matters relevant to commerce and the laws of the UAE.

Prior to setting up Qays H. Zu'bi Attorneys & Legal Consultants in 2001, Qays was the executive resident partner of White & Case LLP, managing its Bahrain office. Here he handled counselling and litigation matters for major financial institutions, multinational corporations and private clients.

Qays has advised private clients in Bahrain and the GCC on a wide range of local, regional and international legal matters. He has extensive experience advising clients doing business in Bahrain and in other Gulf countries. He is currently involved in advising clients in a litigation case in the USA and the UK, and is involved in advising local clients with respect to their assets in France and Azerbaijan.

As a natural progression of his career path, following his knowledge of and experience in the laws of Bahrain and the GCC region, Qays established Qays H. Zu'bi Attorneys & Legal Consultants in 2001, building it into a market leader both in Bahrain and throughout the region. For a short period following his departure from White & Case, Qays' firm was associated with Clifford Chance. On 1 July 2012, he acquired the law practice of Hatim S. Zu'bi & Partners and merged the same with his, today known as Zu'bi & Partners Attorneys & Legal Consultants, the largest local law firm in Bahrain.