Systems and methods for delivering energy to passageways in a patient, such as airways in the lung of a patient for treating asthma. One embodiment of a method for delivering energy to a passageway comprises positioning an access device in a lung airway of a patient and advancing an elongated body of a treatment device along the access device until an energy delivery unit at a distal portion of the elongated body projects from the access device. The method can further include expanding the energy delivery unit such that energy delivery elements contact a sidewall of the airway and activating an energy supply coupled to the treatment device such that energy is delivered to the sidewall of the airway. A single person physically operates both the access device and the treatment device while expanding the energy delivery unit and activating the energy supply.