Sonja Siennick (2009) is Associate Professor in the College of Criminology and Criminal Justice at Florida State University. Dr. Siennick is a life course criminologist with specialties in kinship and friendship relations and the transition to adulthood. She studies the close personal relationships of people who are involved in crime and the criminal justice system. Her research contributes information needed to help offenders preserve potentially beneficial relationships and institutional affiliations and to reduce potential harms to offenders’ significant others. Her current work, funded by the National Institute on Drug Abuse, examines the peer and family factors behind the co-occurrence of internalizing problems with substance use and delinquency during adolescence.