--- - |2+ Abstract The study examines the concurrent and longitudinal associations between ratings‐based measures (parents, secondary caregivers, and observers) and performance‐based measures of focused attention in toddlers aged 30 (n = 147), 36 (n = 127), and 42 months (n = 107). Parents and secondary caregivers rated focused attention behaviours using the Children's Behaviour Questionnaire and observers rated toddlers' focused attention during a series of laboratory tasks using the Leiter‐R Examiner Rating Scale. Toddlers' behaviours on three structured tasks (Token Sort, Toy Play, and Lock Box) were used to assess their performance‐based focused attention in a laboratory setting. Correlations show that parent ratings are not related to observer and teacher ratings or to the performance‐based measures at all ages tested. Second, based on confirmatory factor analyses, a single factor explains the common variance between indicators when the parent ratings are not included in the models. The single factor shows measurement invariance between ages 36 and 42 months based on factor structure, relations of indicators to the factor, and factor scale over time. Third, indicators of focused attention at age 30 months do not seem to measure a common, coherent factor. Interpretations of similarities and differences between ratings and performance‐based indicators of focused attention and the presence of a focused attention construct are discussed. Highlights The concurrent and longitudinal association between ratings and performance‐based attention was examined. Parent‐ratings, observer‐ratings, and performance‐based attention via structured tasks were used. Parent ratings of attention were not related to other ratings, or to the performance‐based measures at all ages; a single factor explains the common variance between indicators when the parent ratings are not included in the models; indicators of focused attention at age 30 months do not seem to measure a common, coherent factor. - Infant and Child Development, EarlyView.