Open classroom sessions foster the development of a common understanding of what good teaching practice looks like. The session may have a specific focus, for example, the use of collaborative learning and flexible spaces. It can also be open-ended and provide a chance to initiate discussion. Promoted by the Hong Kong Association of the Heads of Secondary Schools Limited, our English Panel Head conducted an open classroom session last year. Apart from our Principal, Vice-principal and teacher, there were altogether 12 English teachers of different secondary schools attending the session as observers. After the observation, there were in-depth follow-up discussions.