Which of these is NOT included in the NASW Code of Ethics?

The choice indicating "Impairment of clients" as not included in the NASW Code of Ethics is correct, as the Code focuses primarily on the responsibilities of social workers towards their clients and the broader society, rather than explicitly addressing client impairment itself.

The NASW Code of Ethics emphasizes several core values, among them competence, social justice, and maintaining professional boundaries regarding sexual relationships. Competence underscores the necessity for social workers to maintain and enhance their professional knowledge and skills. Social justice pertains to the obligation of social workers to challenge social injustices and work towards equitable access to resources and opportunities. The guidelines regarding sexual relationships serve to protect the integrity of the social work profession and maintain professional boundaries, ensuring that interactions with clients remain professional and ethical.

Although "impairment" might be a relevant topic within the practice of social work, especially in the context of recognizing and addressing the needs of clients who may be impaired, it is not specifically enumerated as a core ethical standard in the NASW Code. Therefore, this distinction clarifies why "Impairment of clients" is the correct answer in this question.