model describing the relationship between several different theories is the transtheoretical model (Prochaska & DiClemente, 2005). Assimilative integration Assimilative integration is the fourth route and acknowledges that most psychotherapists select a theoretical orientation that serves as their foundation but, with experience, incorporate ideas and strategies from other sources into their practice. "This mode of integration favors a firm grounding in any one system of psychotherapy, but with a willingness to incorporate or assimilate, in a considered fashion, perspectives or practices from other schools" (Messer, 1992, p. 151). Some counselors may prefer the security of one foundational theory as they begin the process of integrative exploration. Formal models of assimilative integration have been described based on a psychodynamic foundation (Frank, 1999; Stricker & Gold, 2005) and based on cognitive behavioral therapy (Castonguay, Newman, Borkovec, Holtforth, & Maramba, 2005). Govrin (2015) pointed out a form of integration, which he called "integration by conversion", whereby theorists import into their own system of psychotherapy a foreign and quite alien concept, but they give the concept a new meaning that allows them to claim that the newly imported concept was really an integral part of their original system of psychotherapy, even if the imported concept significantly changes the original system. Govrin gave as two examples Heinz Kohut's novel emphasis on empathy in psychoanalysis in the 1970s and the novel emphasis on mindfulness and acceptance in "third-wave" cognitive behavioral therapy in the 1990s to 2000s. Other models that combine routes In addition to well-established approaches that fit into the five routes mentioned above, there are newer models that combine aspects of the traditional routes. Clara E. Hill's (2014) three-stage model of helping skills encourages counselors to emphasize skills from different theories during different stages of helping. Hill's model might be considered a combination of theoretical integration and technical eclecticism. The first stage is the exploration stage. This is based on client-centered therapy. The second stage is entitled insight. Interventions used in this stage are based on psychoanalytic therapy. The last stage, the action stage, is based on behavioral therapy. Good and Beitman (2006) described an integrative approach highlighting both core components of effective therapy and specific techniques designed to target clients' particular areas of concern. This approach can be described as an integration of common factors and technical eclecticism. Multitheoretical psychotherapy (Brooks-Harris, 2008) is an integrative model that combines elements of technical eclecticism and theoretical integration.