Symptoms of preschoolers following sexual abuse are not as well documented as for other age groups. This is true both in terms of the associated consequences as well as treatment outcomes. This limitation may be related to the fact that preschoolers represent a subgroup for which it is particularly challenging to substantiate sexual abuse allegations. Younger children also represent a challenge in intervention due to their level of cognitive development and their limited ability to comprehend such complex topics, such as sexuality. Assessing the effects of interventions with this subgroup of children therefore represents a priority in the field. The aim of this paper is to discuss the challenges inherent to the implementation of a cognitive behavioural treatment, namely the Trauma-Focused-Cognitive Behavioural Therapy (TF-CBT; Cohen et al., 2006) with sexually abused preschoolers and to present the results of a pilot study assessing it's effects with a sample of 25 children. Results reveal positive outcomes related to treatment participation both in children and in their accompanying parent. Preschoolers have demonstrated a significant decrease in internalised and externalised behaviour problems as well as a decrease in dissociation symptoms. A significant decrease in psychological distress and post-traumatic stress symptoms was also observed in children's parents following therapy. A follow-up assessment conducted 1 year following the initial assessment revealed that therapeutic gains were maintained over time. Clinical experience highlights specific challenges with preschoolers that are discussed in terms of treatment adaptation.