For the lay public, amyotrophic lateral sclerosis (ALS) appears to be a single disease entity. But clinicians have a front row seat to the heterogeneous clinical presentations that ALS offers up. The differences in presentation make both studying the disease and treating it a challenge. At the annual meeting of AANEM last fall, Matthew Harms, MD , discussed how this clinical variability can be used to better develop care for ALS. The goal, according to Harms, is to break ALS into homogenous subgroups so patients can be assigned to the most appropriate treatments and interventions. Getting to the bottom of clinical variability To achieve the goals of treatment, we need to determine which patients are at risk for which disease course. Who will have a rapid progression of symptoms? Who will experience early speech loss? Who will require early tracheostomy? By looking at subgroups who have a similar disease course, researchers hope to determine if the shared characteristics of the me