This chapter explains the use of psychological theory within a nursing framework to guide them how to how to provide guidance on changing their behavior in day-to-day clinical practice. It suggests that the nurses should get the client/patient to list the positives, when promoting any physical activity. All health care professionals should take the opportunity to identify inactive adults and advise them to aim for 30 minutes of moderate activity 5 days per week and can assess how active the individual is using the GP physical activity questionnaire (GPPAQ). They can assess how active the individual is using the GPPAQ. The answer to this question is the patient's self-efficacy, the positive reasons why change seems possible.