Siya specialises in local government and administrative law, litigation, town planning and development, 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 also a lead 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 is the Vice President of the National Association for Clean Air (NACA), and is a member of the South African Environmental Law Association (ELA), International Association for Impact Assessments South Africa (IAIAsa) and the South African Institute of Occupational Safety and Health.