Siya specialises in local government, town planning and development law, litigation, environmental, clean energy, health and safety law providing legal advice to private and public sector clients, including clients in Europe and North America. Siya has litigated up to the Constitutional Court. He is a Principal auditor for SHE Legal Compliance audits conducted for various national and international companies across South Africa, and in foreign jurisdictions such as Namibia, Zambia, Botswana and Lesotho. He provides training on a variety of legal topics and has been invited by national and international Institutions as a guest speaker and lecturer.

Service on Boards and Association: Siya serves as the President of the National Association for Clean Air (NACA) and is the Chairperson of the J Reuben Clark Law Society in the Africa South Area. He is also a Trustee of the Sibudu Trust, which aims to preserve the Sibudu Cave (a UNESCO World Heritage site). Siya assisted with several processes to have the Sibudu Caves declared a national and world heritage site. Siya is a member of the South African Environmental Law Association (ELA), the South African Institute of Occupational Safety and Health, and the International Association for Impact Assessments South Africa (IAIAsa).