A method is described for modifying at least one property of a tissue of or near a nasal valve of a nose, without using a surgical incision or an implant, to decrease airflow resistance or perceived airflow resistance in a nasal airway. The method may involve contacting a treatment element of a treatment device with the at least one tissue inside the nasal airway, with sufficient force to at least temporarily deform the at least one tissue, applying energy to, or removing energy from, the at least one tissue, using the treatment element, and removing the treatment element from the nostril.