The accuracy of adolescent and parental reports of youth secondhand smoke exposure has received limited attention in the research literature. Florida Youth Cohort Study participants provided saliva samples during the fifth round of interviews for determination of cotinine levels. After exclusion of admitted or likely youth smokers with cotinine levels>14.7 ng/ml, there were 341 youth ages 13-17 who completed a telephone interview; 304 parents of these participants completed a similar secondhand smoke exposure interview. Adolescents with cotinine levels above the threshold of detection (> 0.10 ng/ml) were considered exposed. Specificity ranged from 87.1-97.8. Positive predictive value, negative predictive value, sensitivity, and kappa values varied considerably by the reporting source (e.g., youth, parent, or a combination of responses), and the age and gender of the youth respondent. Agreement between youth and parent that at least one parent smoked inside the home yielded the best combination of sensitivity (85.0) and specificity (89.8) and was least affected by the age and gender of the youth respondent.