Case management is one of the principal components of service delivery in mental health services. Over time, it has evolved into new models, and various meta-analytic studies have been carried out to establish its effects. Those studies have yielded non-homogeneous results, which might be related in part to the progress of case management models. Therefore, there is a need to understand the relationship between CM models and CM effects. This paper deals with this issue by reviewing and updating the literature regarding case management models and effects in order to help understand its current role and suggest how CM could be reorganized. Assertive community treatment and any other case management model seem to have fused and turned into two models that differ mainly with regard to the intensity of care provided to patients. The results of the meta-analyses on the efficacy/effectiveness of case management are not homogeneous across all studies, which seems to be related to the case management model used and the strictness of the methodology followed. When the model of case management used is congruent with clinical practice, the results favor case management over standard care and show that intensive and non-intensive case management may be provided depending on the previous use of hospital resources. Our paper suggests that case management models could be reconfigured by offering an intensity of care based on patients'needs.