Purpose: In working with children with language impairments, some clinical scholars and clinicians advocate using input that is simplified to the point of being ungrammatical (telegraphic input), while others advocate simplified but grammatical input. This article considers 2 types of external evidence on this topic. Method: First, a meta-analysis of relevant research, including intervention studies and processing studies, is reported. Next, 4 experts present their opinions. Results: Children in the majority of the intervention studies showed no difference in language comprehension based on type of input, although 1 study with very few children favored telegraphic input for language production. In the processing studies, which measured immediate comprehension, children from clinical populations responded inconsistently when listening to the 2 types of input. Children who had typical language, however, favored grammatical input in their responses. Regarding the experts' opinions, 2 suggest that telegraphic input is sometimes warranted; 1, who previously indirectly promoted its occasional use, no longer believes it should be used; and 1 provides reasons why telegraphic input should not be used and may even be harmful. Conclusions: Empirical findings and expert views are summarized as ways of informing parents of the weak evidence base regarding the best type of input.