Mr. Zhang is very good at handling difficult and complex cases in litigation fields of trade mark, copyright (computer software, protection of music and audiovisual products), unfair competition (protection of famous commodity and commercial secrets), and has accumulated rich experience in lawyer’s profession. Mr. Zhang has made efforts to safeguard rights and defused disputes by handling lots of intellectual property cases based on spirits of integrity, respect and friendliness.Since 2009, six IP cases represented by Zhang Yazhou have been selected by the Supreme Court as one of the top ten IP cases of the year, and several other cases have been selected by provincial high courts as one of the top ten IP cases of the year.

In October of 2009, Mr. Zhang attended the “Lecture of Execution of Civil Right” held together by Agency for Cultural Affairs, Government of Japan and Japan External Trade Organization (JETRO) in Tokyo upon the invitation of JETRO and gave speech about Legal Issues Involved in Network Copyright Infringement of China; in February of 2012, Mr. Zhang attended the “Intellectual Property Salon and the 134th INTA Annual Meeting in Washington” to participate in the discussion about Issues on Trademark Infringement and Determination of Liability for Damages of Vendors upon the invitation of INTA (International Trademark Association); in September of 2013, Mr. Zhang gave speech about China's legal issues involved in typical cases of litigations about trademark infringement in recent years in Seoul upon the invitation of Korea Invention Promotion Association(KIPA).

Mr. Zhang also successively published many articles on various professional journals, magazines and newspapers, including Several Issues on Assessment of Damages in Trademark Infringement Cases, Observation on Application of Article 5.2 of Anti-Unfair Competition Law from Special Package and Decoration of Well-known Goods “FERRERO ROCHER” Chocolate, On Relevant Issues regarding POCO Software (P2P Sofware), Introduction on Legal Mechanism on Protection of Audiovisual Products in China, Analysis on Protection of Bona Fide Third Party in Transfer of Technical Secrets.