Aim The aim of the study was to develop an ecologically valid synthesis of the evidence underpinning interventions for children with speech, language, and communication needs ( SLCN), integrating a range of different data sources. Method Three sources of information were integrated: the Cochrane Review of interventions for children with primary speech and language delays/disorder; current practice from an online survey of 534 speech and language therapists and other professionals working with children with SLCN; and parent reports of preferred outcomes. Evidence was ranked as strong, moderate, or indicative. Results Of the 58 interventions identified, three (5%) were found to have a strong level of evidence, 32 (56%) had moderate evidence, and 23 (39%) had indicative evidence. Five were universal interventions, the remainder targeted and universal. The integrated findings were then turned into an online interactive database, which is moderated and updated at regular intervals. Interpretation There are a number of interventions that have a moderate or strong level of evidence underpinning them but they tend not to be those used by practitioners who often favour well-established familiar programmes even if they have only indicative evidence. There is a degree of complementarity between professional and parent views about outcomes, albeit with different emphases. [ABSTRACT FROM AUTHOR]