Relational disturbance, as encountered across the depth-psychology corpus, names a broad family of disruptions in the capacity for healthy interpersonal connection — disruptions that are at once neurobiological, developmental, intrapsychic, and systemic in origin. The literature does not converge on a single definition; rather, it triangulates the phenomenon from several directions. Porges and Dana locate relational disturbance at the autonomic level, where violations of neural expectancy produce rupture between nervous systems in lieu of resonance. Siegel situates it within the developmental architecture of the brain, arguing that the absence of adequate rupture-and-repair cycles leaves integrative structures impaired and relational life oscillating between chaos and rigidity. Herman and Lanius ground it in interpersonal trauma — abuse, neglect, disorganized attachment — that reshapes affect regulation and self-structure, yielding the complex sequelae later theorized as developmental trauma disorder. Ogden and Dayton foreground the procedural and familial dimensions: implicit relational knowing encoded in early caregiving becomes the invisible script through which disturbance re-enacts itself across generations and across the transference field. Running through all these positions is a common claim — that relational disturbance is not merely symptomatic but constitutive, shaping identity, somatic organisation, and the very templates by which future connection is sought or avoided.