Background: Oral comprehension difficulties are prevalent in preschool children with language difficulties and are frequently the target of speech and language therapy (SLT) intervention. To support the implementation of research to practice, there is a need to identify effective interventions for this population and to describe their components. To date, reviews of oral comprehension intervention have not used inclusion criteria aligned with common clinical practice, particularly in the United Kingdom. No studies have previously used the Template for Intervention Description and Replication (TIDieR) checklist to describe developmental SLT interventions. Aims: To identify intervention studies effective for oral comprehension in preschool children with language difficulties, using the UK definition of 'preschool' as children under 5 years; to describe the components of these interventions. Method: This followed two phases: (1) an International Prospective Register of Systematic Reviews registered search, which identified 20 systematic reviews; and (2) an exploration of individual studies within these reviews. Seventeen individual studies described effective intervention for children from 1 to 5 years old with language difficulties. Data were extracted from each study against headings from the TIDieR checklist. Findings were analysed and reported using narrative synthesis. Main contribution: A wide variety of rationales, techniques, procedures, settings and intensities were associated with effective intervention. The TIDieR checklist highlighted components that were unreported or under-described. Conclusions: Studies show that intervention can be effective for improving oral comprehension in preschool children with language difficulties. Analysis of intervention components has relevance to clinical practice and research, and highlights the importance of naturally occurring interactions, cross-over between oral comprehension and expressive language and the variety in delivery models and dosage.