Jannie van der Sleen received her MSc. in clinical psychology from the University of Groningen and then worked for 15 years as a behavioral science teacher at the Rechercheschool in Zutphen. There she taught in the field of report, witness and suspect interrogation, specializing in interrogations in vice cases and interrogations of minors.

Since 2002, Van der Sleen has been working independently within her company Kinterview (www.kinterview.com). Commissioned by the Police Academy, she supervises investigators who have to interrogate minors In addition, she provides education for various organizations regarding conducting interviews with vulnerable persons. She is head trainer of the Criminal Investigation Psychologist course at the RINO Group in Utrecht. Van der Sleen also acts as an expert in criminal investigations. She reports in such cases on the value of statements of declarants, witnesses and suspects.

In addition to her work for Kinterview, Van der Sleen works closely with Dantes Psychology. She assists in investigations of behavior of concern, especially in the assessment of the behavior and statements of minors and when minors need to be interviewed. She provides training regarding transgressive behavior within organizations.