Asthma and atopic dermatitis are common childhood diseases requiring long-term treatment. Adherence to treatment is often poor. Written action plans (WAPs) can improve adherence in pediatric asthma. In this article we review the use of WAPs in pediatric asthma and atopic dermatitis as a basis for assessing WAPs for pediatric patients with atopic dermatitis. Results from a PubMed search for WAPs in pediatric asthma and a Cochrane review on this topic were compiled. Results from a PubMed search for education in pediatric atopic dermatitis were also reviewed. The preponderance of evidence indicates that WAPs improve adherence in pediatric asthma. No such intervention was identified for atopic dermatitis. Few controlled trials directly comparing use to non-use of a WAP were found. WAPs show promise in improving adherence in pediatric asthma, and their effect on adherence in pediatric atopic dermatitis is worthy of further investigation.