There is currently insufficient evidence for the use of a specific pharmacological treatment for personality disorders (PD). The research literature lacks a systematic exploration of clinicians' experiences of pharmacological treatment of PD. The aim of the qualitative study was to examine how psychiatrists make decisions about pharmacological treatment for patients with PD. The interviews were analyzed using inductive thematic analysis. The results showed that ambiguous guidelines had the effect that the psychiatrists often relied on their own experience, or that of their colleagues. As a basis for decisions concerning drug treatment, an interpersonal component was also identified. Some of the psychiatrists in the current study argued that medications may be part of the alliance-building with the patient and that medications were a way of tying the patient to the clinic. Our findings show that it is important to work on how the clinical guidelines should be implemented in practice.