Vajrayāna Buddhism is esoteric in the sense that the transmission of certain teachings only occurs directly from teacher to student during an empowerment ("abhiṣeka") and their practice requires initiation in a ritual space containing the mandala of the deity. Many techniques are also commonly said to be secret, but some Vajrayana teachers have responded that secrecy itself is not important and only a side-effect of the reality that the techniques have no validity outside the teacher-student lineage. In order to engage in Vajrayāna practice, a student should have received such an initiation or permission: