An overview is given of the following four well-defined diagnostic subgroups of patients who have craniomandibular disorders: those with a mainly myogenous component; those with internal derangement with reduction; this with internal derangement without reduction; and those with osteoarthrosis. Although it was inevitable that the subgroups were not completely homogeneous, symptom profiles differed considerably. There even seemed to be reasons to distinguish two osteoarthrosis groups in future research. Although the identification of clinically significant factors in a given patient with craniomandibular disorders remains a difficult clinical task, the symptom profiles provide a framework that may give more insight into the background of the complaint and into possible contributing factors. The symptom profiles also provide the possibility of a more directed choice of treatment and a treatment evaluation that is more aimed at the specific characteristics of the subgroups. It therefore may be concluded that, to increase insight into craniomandibular disorders, the evaluation of diagnostic subgroups has to be preferred in the assessment of a heterogeneous group of patients with craniomandibular disorders.