The aims of the current study was to investigate the relation between the narcissistic personality syndrome (NPS) and schema modes, which refer to the predominant emotional state, schemas, and coping responses that are active for an individual at a particular time. Participants consisted of 25 clients who filled out the Schema Mode Inventory and 25 clinicians who provided assessment of NPS using the Shedler-Westen Assessment Procedure. This study showed a significant correlation between NPS and a lack of frustration tolerance (i.e., undisciplined child mode). There were no significant relations with self-aggrandizement (i.e., self-aggrandizer mode), feeling intensely angry (i.e., angry child and enraged child modes), and trying to suppress painful emotions by compulsively and excessively committing to distracting and soothing activities, such as abusing drugs (i.e., detached self-soother mode). This preliminary study contributes to our understanding of pathological narcissism in Dutch outpatient clients. We point to the importance of a self-reported lack of frustration tolerance as a potentially valuable diagnostic characteristic of pathological narcissism. We additionally emphasize the importance of diagnostic approaches based on clinical judgement when it comes to pathological narcissism.