Individual counseling is the primary intervention of the practice component of the scientist–practitioner model and a frequent focus of research related to the scientific component. A timeline of historical events shaping individual counseling is presented, followed by an examination of commonalities across schools of therapy that define this intervention. These include why clients seek counseling; the therapeutic relationship; client expectancies; micro-skills; facilitating emotions, insight, and change in counseling; phases of counseling; and extra-therapeutic factors. The role of theory, with its focus on specific or unique effects, is examined and contrasted to the common factors approach. Conclusions and recommendations for future research are presented, including those areas in which there is some degree of consensus (e.g., need for research on the role of the relationship and insight) and areas in which there is divergence (e.g., specific or unique factors vs. common factors; transferability of evidence-based treatments to clinical settings; single theory vs. integrationist approaches).