In addition to a horizontal model (Model1, Chap. 3) about width in relationships, Model2 is concerned with viewing relational competence (RC) according to a layered perspective composed of levels of observation and interpretation for how RC varies along a vertical dimension of depth. This multilayered model comprises two major levels of description and explanation. Each level has two sublevels. The literature about this vertical model composed of two levels and two sublevels has been reviewed repeatedly and at length in previous publications by the first author and only more recent evidence about each sublevel will be included here. The reader interested in greater detail about this model is referred to previous publications, especially the most recent and detailed one (L’Abate, 2005).