A method and apparatus for transporting single and multiple reaction vessels, wherein at least one reaction vessel (9), at least one tray (31) comprising at least two seats (27) for the at least one reaction vessel (9), and at least one gripper (44) are provided. One of the reaction vessel (9) or the tray (31) is engaged with the gripper (44) at a first position, the gripped element (9, 31) is transported to a second position and the gripper (44) is released. A similar gripping collar (16) is provided both on the reaction vessel (9) and the tray (31) for the gripper (44) to engage. At one transport stage one of the reaction vessel (9) or the tray (31) is engaged with the gripper (44) at a first position by pushing the gripper (44) from above to engage with the gripping collar (16) for the gripper (44) and in a second stage the transported element (9, 31) is disengaged from the gripper (44) by moving the gripper (44) sideways in relation to the center axis of the gripping collar (16).