Counselors have many roles to play in their jobs; one of the most important being the evaluation of programs' effectiveness for the clients they serve. Program evaluations collect and analyze quantitative and qualitative data to measure and determine program effectiveness and efficiency. Counselors conduct evaluations for the purpose of measuring the value of a program, its activities, and the staff who implement it, in order to decide if the program is viable and worth continuing. These evaluations are also used to determine if changes should be made to a program the next time it is run