The effects of a parent-coached language intervention on parent stress and its relation to parent perceptions of communication development were examined in 60 parents of toddlers with developmental delays. Results indicated that overall parent stress was not high prior to or following language intervention. Parents' perceptions about the severity of their children's communication deficits partially mediated the relationship between expressive language at preintervention and parent stress at postintervention. Parents of children who had better expressive language at the beginning of intervention perceived their children's communication difficulties as less severe and had less parent stress following language intervention. (Contains 6 tables.)