Abstract: Via a trachea (5) of the subject, an end of a first tube (120) is advanced along a first airway route (127) to an imaging site (20) within the lung (55). Independently of the first tube, an end of a second tube (130) is advanced along a second airway route (130) to a tool site (30) within the lung. While the first tube remains extended along the first route and the second tube remains extended along the second route, an imaging device (128), extended from the end of the first tube, is used to image a tool (138) extended from the end of the second tube, and a target (40) within the lung. The tool can be used to perform a procedure on the target, guided by the imaging of the target and the tool. Other embodiments are also described.