To compare the effectiveness of lavender ( Lavandula angustifolia) and sleep hygiene versus sleep hygiene alone on sleep quantity and sleep quality and to determine sustained effect at two-week follow-up. Design: A randomized controlled trial with investigator blinding and steps taken to blind the participants. Setting: Participants' usual sleep setting. Subjects: Seventy-nine college students with self-reported sleep issues. Interventions: The intervention took place over five nights with baseline, postintervention, and two-week follow-up assessments. Both groups practiced good sleep hygiene and wore an inhalation patch on their chest at night. One group wore a patch with 55 μl of lavender essential oil and the other group wore a blank patch. Outcome measures: Sleep quantity was measured using a Fitbit® tracker and a sleep diary, and sleep quality was measured using the Pittsburgh Sleep Quality Index (PSQI) and the NIH Patient-Reported Outcomes Measurement Information System (PROMIS) sleep disturbance short form. Results: The lavender and sleep hygiene group demonstrated better sleep quality at postintervention and two-week follow-up (PSQI p=0 .01,