A persistent focus on order and rules, often at the expense of flexibility, describes which disorder?

The description of a persistent focus on order and rules, often at the expense of flexibility, aligns with Obsessive-Compulsive Personality Disorder (OCPD). Individuals with OCPD exhibit a pervasive pattern of preoccupation with orderliness, perfectionism, and control over their environment and behaviors. This can manifest in an excessive devotion to work and productivity, rigidity in their moral and ethical beliefs, and an insistence on rules and procedures being followed strictly.

In contrast, the other disorders mentioned focus on different core symptoms. Avoidant Personality Disorder is characterized by feelings of inadequacy and hypersensitivity to negative evaluation rather than a rigid adherence to rules. Narcissistic Personality Disorder involves a grandiose sense of self-importance and a need for admiration, focusing on self-centeredness rather than an emphasis on order. Dependent Personality Disorder is marked by an excessive need to be taken care of, leading to submissive and clingy behaviors, not a fixation on rules or order.

Therefore, the defining characteristics of OCPD fit perfectly with the question, highlighting the rigidity and strong adherence to structure at the cost of flexibility.