Emotional knowledge about one's own and others' emotional experience are central features of mental health and may be characteristic of therapeutic processes leading to good outcome. Clients with personality disorders (PDs) often lack in their ability to access and accept emotional experiences, or to reflect on emotion and use it in adaptive ways. The present theoretical and clinical review discusses self-knowledge, and lack thereof, in personality disorders, from an emotion-focused perspective. A first section differentiates between two fundamental types of meaning construction processing. The second section describes, from an integrative therapy perspective, how self-knowledge may be facilitated in psychotherapy by the client-therapist interaction. A subsequent section discusses lack of awareness of one's own emotions in the construction of meaning associated with PDs. The final section describes initial studies that demonstrate change occurring in constructing emotional self-knowledge as a correlate of treatment. The concepts of the review are illustrated throughout with three clinical cases of PD.