Acceptability of medicines in children and caregivers affects safety and effectiveness of medicinal treatments. The pharmaceutical industry is required to demonstrate acceptability of new paediatric formulations in target age groups as an integrated part of the development of these products (Kozarewicz, 2014). Two questions arise when trying to tackle this task: "which dosage form to choose for each target age group?" and "how to formulate it once the dosage form is decided?". Inevitably, both the regulator and the developer turn to scientific evidence for answers. Research has emerged in recent years to demonstrate age-appropriateness and patient acceptability of different dosage forms; however, such information is still fragmented and far from satisfactory to define efficient formulation development strategies for a diverse patient subset (Ranmal and Tuleu, 2013). This paper highlights how formulation factors affect the acceptability of different oral medicines in children (Table 1), and it is based on a more extensive review article by Liu et al. (Liu et al., 2014). Gaps in knowledge are highlighted in order to stimulate further research. In some areas, findings from studies conducted in adult populations may provide useful guidance for paediatric development and this is also discussed.