We examine why science is important to applied psychology, even if one’s motivation to be a psychologist is primarily practical. Helping others takes knowledge and skill, and often applied psychologists face situations that do not produce immediate or clear outcomes. In such situations experiential learning can only do so much, and science is needed to be effective long term. When the history of training models in applied psychology is reviewed from the inception of the field to the present day, it is clear that students of applied psychology need to learn how to do research that will inform practice, how to assimilate the research evidence as it emerges, and how to incorporate empiricism into practice itself. We argue that the kind of knowledge needed by practitioners requires a focus on the needs of those served by psychologists, a more personalized and process-based research approach, and a laser-like focus on issues of broad importance. A scientist-practitioner is a consumer of research, but is also able to identify, acquire, develop, and apply empirically supported treatments and assessments to those in need, and to think about their own work with an empirical mind set.

The chapter outlines low intensity psychological Interventions (LIPIs). These are treatments that have low usage of a specialist’s therapist time (e.g., 5–8 sessions), or uses the time in a manner that reaches a large number of people. Low intensity does not refer to the client’s experience. Even though the contact with the specialist is less, the client’s involvement in terms of time, effort and emotional investment can be intense. The chapter outlines in a practical manner stepped-care, how to offer choice to service users, and shared decision-making. Given that LIPIs can be challenging to master, the chapter provides an illustrative example of adapting case formulation and treatment planning to this mode of delivery.

The chapter outlines an evidence-based approach for clinical psychologists to select and provide group treatments. The process begins with selecting the appropriate treatment programme and then selecting the appropriate patients for the group. The chapter will identify principles for selection and assessment as well as how the use of interpersonal interaction as a therapeutic tool in the here-and-now context of a group can be an inherent advantage of group interventions.In addition, it outlines practical steps for implementation of a group that includes pre-group orientation, enlisting patients as informed allies, providing guidelines about how best to participate, clarifying the format and duration, setting ground rules, anticipating problems and instilling optimism among members. The chapter concludes with a consideration of how monitoring of process and outcomes can enhance outcomes.