This chapter provides an overview concerning the historical development of consultation-liaison psychiatry (CLP) and details the meaning of consultation and liaison activity. The procedure of consultation is detailed. Several assessment tools that support clinical investigation are presented and discussed. Specifically, the assessment of personality traits, anxiety and depressive symptoms, and other psychological factors are addressed. As far as clinical research is considered, two topics are presented: CLP within the psycho-neuro-endocrine-immune perspective and CLP in the field of transplants. Finally, special attention is dedicated to the impact of CLP on health care budgets and to the role played by CLP in end-of-life care. Several skills are required in the field of CLP. Some are general (e.g., assessment of psychiatric diagnosis and medical-psychiatric comorbidity, use of psychopharmacological treatments, etc.); others are specific to the setting (e.g., transplantation, end-of-life-care, etc.). Once acquired, both general and specific skills may be implemented in psychiatric settings other than the CLP, thus representing professional assets potentially useful in all psychiatric settings. Therefore, CLP should be considered not only as a subspecialty of psychiatry, but also as a forma mentis, a professional attitude that the psychiatrist may implement in several psychiatric settings.

Although academic obstetrician-gynecologists were important advocates for legal abortion, few teaching hospitals became sources of abortion care in the USA. Instead, private clinics provided nearly all abortions and medical students and residents had little opportunity to learn about abortion.Likewise, when contraception was earlier legalized, the major sources became Planned Parenthood and public health department clinics funded through the US Government’s Title X Program.Academic organizations responsible for training obstetrician-gynecologists recognized these deficiencies and moved to require training in family planning and to set standards for it.A few major teaching hospitals provided models for such training.Their efforts were emulated and financially supported at training programs around the USA through the “Ryan Residency Training Program in Abortion and Contraception” reaching one hundred programs over a 20-year effort.Because teaching hospitals largely ignored abortion and their reproductive endocrinologists were busy with IVF, academic training programs failed to develop researchers in abortion and contraception.In response to the need for clinical research and teaching in family planning, post-residency fellowship programs were simultaneously established in 30 medical schools, eventually leading to recognition in 2020 of “Complex Family Planning” as one of the official subspecialties of obstetrics and gynecology.