Abstract : Impaired, stereotypical motor coordination emerges during stroke recovery due to abnormal co-activation of muscles, a key contributor to motor impairment in over 7 million stroke survivors in the US. Spontaneous recovery does not fully resolve abnormal muscle coordination. Thus, there is a critical need to develop effective ways to reduce impaired muscle coordination for stroke recovery. Our previous studies show that under isometric conditions, stroke alters motor modules: coordinated patterns of muscle activity that flexibly combine to produce functional motor behaviors. Prevalence of the alteration depends on the severity of motor impairment in stroke survivors. Can we utilize the characteristics of muscle coordination in stroke survivors, different from that of the age-matched control subjects, to improve motor function of stroke survivors? What experiments can or should be done to test whether the characteristics of muscle coordination can be used to design new therapeutic protocols to improve motor function post-stroke? In this seminar, I will discuss the neuroscientific background of motor coordination in stroke survivors, present some preliminary data on modifiability of habitual intermuscular coordination, and propose how the nature of motor coordination may be utilized to improve movement quality in stroke survivors.