<p>This research evaluates the Ready4Routines Intervention Program’s effectiveness in enhancing executive function skills among preschoolers, reducing parental stress, and fostering autonomy-supportive parenting by improving mothers’ ability to organize family routines in socioeconomically disadvantaged areas of Ankara, Türkiye. This mixed-method study included 36 mother-child dyads (children aged 48–60 months; 19 in the intervention group and 17 in the control group). The sample was assessed using the Child Executive Functions Development Scale, Autonomy-Supportive Parenting Scale, Parenting Stress Scale, and a Semi-Structured Interview Form on family routines. The Ready4Routines intervention program was implemented in a preschool over 10 weeks. Mothers in the intervention group practiced the activity cards at home with their children during family routines, such as transition times, mealtimes, and sleep or wake times. The control group did not receive the intervention during this period. Data were analyzed using the Wilcoxon Signed-Rank Test for quantitative measures and content analysis for qualitative interviews. Pretest, posttest, and six-week retention test results indicated significant improvements in children’s executive functions—including working memory, self-regulation, and empathy/inhibition—along with better organization of family routines and decreased maternal stress in the intervention group. Qualitative findings revealed that mothers reported greater confidence in managing daily routines and observed increased cooperation and engagement from their children. Overall, the Ready4Routines intervention program is an effective approach for supporting child development and enhancing family well-being through the reduction of parental stress and the promotion of structured family routines.</p>