The purpose of this meta-analysis was to determine whether experimentally tested sightreading interventions positively influenced sightreading ability. A meta-analysis was conducted with 92 quasi-experimental research studies on sightreading (124 individual analyses) to determine the overall effect size of treatment and to examine how the effect size was influenced by treatment type, sightreading mode (sightreading/sightsinging), age and experience of sight reader, type of sightreading test, and other study design elements. The analysis revealed a small overall effect size for treatment (d = –0.18, 95% CI [–0.24, –0.11]). Of the moderator variables, only treatment-type was significant, with treatments categorized as "Aural Training," "Controlled Reading," "Creative Activities," and "Singing/Solfege" significantly and positively affecting sightreading. There was a moderately strong within-group effect size (d = –0.48, 95% CI [–0.56, –0.40]), indicating that sightreading generally improved pre- to posttest for both control and treatment groups.