This study examined the "Parenting the Strong-Willed Child" ("PSWC") book as a self-directed program for parents of 3- to 6-year-olds. Fifty-two parents were randomly assigned to "PSWC" or a comparison book, "Touchpoints: Three to Six." Assessments occurred at baseline, postintervention (6 weeks after baseline), and 2-month follow-up. The findings indicated both books, but particularly "PSWC," were associated with lower levels of child problem behavior after intervention. "PSWC" was associated with greater decreases in child problem behaviors on certain measures when amount of reading completed was taken into account. Parents reading "PSWC" reported that they were satisfied with the book and found the book useful and easy to implement. The findings are discussed in the contexts of both the percentage of parents who read the "PSWC" book and the cost-effectiveness of a self-directed intervention. (Contains 3 tables and 1 figure.)