This article reports a series of interviews with education and health practitioners. The aims were to identify interventions used in practice with children with speech, language and communication needs, to explore explanations for the choice of intervention and to identify the ways that outcomes were measured. Participants (n = 61) included educational psychologists, speech and language therapists and education advisory staff. They talked about interventions in terms of published programmes, principles and activities, strategies, resources and training programmes. There was evidence of local adaptation of interventions and wide development of local programmes. The choice of intervention was governed by a desire to meet identified service gaps and with reference to the evidential and/or theoretical basis of the intervention and the practicalities of the intervention. Outcomes were typically measured at the level of the individual rather than a service level. The study provided insight into the range of interventions in current practice, how service managers justify intervention choices and measure outcomes. The data from this study informed a national survey to examine patterns of usage of interventions.