Webinar: Update in WHO Breast Tumours Classification and Immunohistochemistry was held in Sunday, 2 August 2020. Topics and presenters were:1. Adequate analytic process for immunohistochemistry (dr. Erika Paskarani, Sp.PA)2. ER & PR immunohistochemistry in breast carcinoma (update) (dr. Luh Dewi Rahayu, Sp.PA)3. HER2 immunohistochemistry in breast carcinoma (update) (dr. Luh Dewi Rahayu, Sp.PA)4. Ki67 immunohistochemistry in breast carcinoma (update) (DR. dr. IGA Sri Mahendra Dewi, Sp.PA(K))5. WHO classification of breast tumours (update) (Dr. dr. Ni Putu Sriwidyani, Sp.PA)6. Experience in immunohistochemistry in some centers (dr. Kadek Pramesti, Sp.PA)7. Standard reporting system in breast carcinoma immunohistochemistry (dr Mahastuti, Sp.PA)