This chapter focuses on assessment as an overall and ongoing process and includes testing as a component of the entire assessment process including collecting information through multiple methods. Multiple methods, both formal and informal, allow counselors to measure human concepts such as emotion, intelligence, personality, self-esteem, and aptitude. The process of using subjective information plays an important part in the counseling process and using objective assessment can also facilitate and enhance counselors' work with clients and improve the efficacy of their counseling. Other purposes include career interests, assessment of ability or achievement, intelligence, or personality, which can provide more information about the client that enhances the counseling process. Using assessment in counseling has several distinct advantages over other types of counselor interactions and data gathering with clients. Assessment can provide insight for the client and counselor, all with the goal of promoting and improving the client's well-being.