The objective of this study was to characterize the population of multiple sclerosis (MS) patients suffering from spasticity and to evaluate treatment patterns, including intrathecal baclofen (ITB) delivery, related to patient quality of life (QOL). We conducted a cross-sectional, two-level study using data from the Patient Registry of the North American Research Committee on MS (NARCOMS). In addition, we surveyed a subgroup of 198 preselected patients who are using ITB (ITBG) and a random sample of 315 oral drug users (ORALG). Among the registrants, 16% reported no spasticity, 31% minimal, 19% mild, 17% moderate (frequently affects activities), 13% severe (daily forced to modify activities) and 4% total (prevents daily activities). Patients experiencing greater severity included by proportion males, and those older and with longer duration of MS. QOL scores decreased inversely with severity. In the focused survey, ITBG reported lower levels of spasticity than ORALG, less stiffness in the legs, less pain and fewer spasms at any time. They scored significantly lower in the SF-36 physical component, yet reported less fatigue on the MFIS scale. Prevalence data reveal that one third of MS patients modify or eliminate daily activities as a result of spasticity. Treatment of spasticity can significantly impact QOL parameters by reducing spasms, pain and fatigue.