This paper proposes that idiographic graphical representations of psychological change should complement psychometric test scores in the forensic context. In particular, it is argued that idiographic procedures offer sensitive and precisely targeted assessments. We attempt to show, in a didactic manner, the way in which a technique like Multiple Card Sorting (MCS) may provide both qualitative and quantitative insights into the change exhibited by a single patient. The information returned from this assessment is qualitative but highly structured and may be used to inform treatment planning and evaluation..