Abstract Objective To examine the effect of a shared decision-making intervention with parents of children newly diagnosed with attention-deficit/hyperactivity disorder. Methods Seven pediatricians participated in a pre/post open trial of decision aids for use before and during the office visit to discuss diagnosis and develop a treatment plan. Encounters pre- ( n = 21, control group) and post-intervention implementation ( n = 33, intervention group) were compared. We video-recorded encounters and surveyed parents. Results Compared to controls, intervention group parents were more involved in shared decision-making (31.2 vs. 43.8 on OPTION score, p < 0.01), more knowledgeable (6.4 vs. 8.1 questions correct, p < 0.01), and less conflicted about treatment options (16.2 vs. 10.7 on decisional conflict total score, p = 0.06). Visit duration was unchanged (41.0 vs. 41.6 min, p = 0.75). There were no significant differences in the median number of follow-up visits (0 vs. 1 visits, p = 0.08), or the proportion of children with medication titration (62% vs. 76%, p = 0.28), or parent-completed behavior rating scale to assess treatment response (24% vs. 39%, p = 0.36). Conclusions Our intervention increased shared decision-making with parents. Parents were better informed about treatment options without increasing visit duration. Practice implications Interventions are available to prepare parents for visits and enable physicians to elicit parent preferences and involvement in decision-making.