<p>The aim of this study was to gather participant feedback to enhance the Lights Out Online Program, a 4-session, self-directed, web-based parent intervention targeting behavioural sleep problems in preschool-aged children using evidence-based strategies. Specifically, we sought to (1) understand parents’ experiences with the program itself, including their level of satisfaction and their implementation of program strategies, and (2) gain feedback from parents regarding possible program improvements, to inform improvements and adjustments to the program. Data were collected using session satisfaction surveys at the end of each session, complemented by videoconference interviews with a subset of participants to understand implementation of program strategies following program completion. Twenty-four parents of children aged 3–6 years with sleep problems participated in the program, six of whom also participated in a semi-structured interview. Deductive organisation of survey responses revealed that the program was practical, and that the strategies were easy to implement; however, parents found sessions most helpful when the content related to their child’s specific problem. Using a reflexive thematic analysis, four main themes were captured in the interviews: (1) the cascade of positive changes following program completion, (2) the gradual process required for successful implementation and change, (3) the invitation for all parents to be on the same page, and (4) the need for flexibility in delivery. The areas for improvement suggested by parents were incorporated into the revised online program. This revised version of Lights Out Online has the potential to increase acceptability, engagement, and long-term adoption of the program.</p>