This paper focuses on the issue of trust (Vertrauen) and trustworthiness (Zuverlässigkeit) in Nicolai Hartmann’s stratified ontology. Our analysis will start with Hartmann’s Ethics (1926) and then discuss parts of Das Problem des geistigen Seins (1933) and Philosophie der Natur (1950). In his mature works, Hartmann approaches the axiological situation of trust from the viewpoint of the permanence of all elements involved in it: trust as an ideal value, the tangible goods that substantiate a relationship of trust, the other persons and, finally, the moral subject or person (for others to trust me, my personal identity must be stable). From this viewpoint, for trust to be made real it is the whole ontological context that, notwithstanding its processuality, has to guarantee a (relative) ontological stability. This approach gives Hartmann the opportunity to address a harsh criticism to philosophical substantialism and to develop an innovative view of the modality of ontological persistence of the person.