Methods and devices are provided for facilitating movement of a surgical tool through a tortuous pathway in the body. The devices and methods disclosed herein can be used in conventional, open surgical procedures, and they are particularly useful in minimally invasive surgical procedures, such as endoscopic procedures. In one aspect, the movement of the device relative to tissue is effected by applying suction to draw tissue to the device thus straightening the passageway. The suction can be removed or reduced and then the device can be further advanced along the passageway.